FCC ID: T7HHT7254 Wireless Mono Headset, Wireless Stereo Headset, Wireless Stereo ANC Headset

High-End Headset Guide for RTX725x Installation & Configuration Network Deployment Operation & Management Technical Reference Document Version 1.0 Apr-2020 RTX A/S, Denmark RTX725x GUIDE 1.0 Proprietary and Confidential Trademarks RTX and the combinations of its logo thereof are trademarks of RTX A/S, Denmark. Other product names used in this publication are for identification purposes and maybe the trademarks of their respective companies. Disclaimer The contents of this document are provided about RTX products. RTX makes no representations with respect to completeness or accuracy of the contents of this publication and reserves the right to make changes to product descriptions, usage, etc., at any time without notice. No license, whether express, implied, to any intellectual property rights are granted by this publication Confidentiality This document should be regarded as confidential, unauthorized copying is not allowed Apr-2020 RTX A/S, Denmark, All rights reserved http://www.rtx.dk RTX725x GUIDE 1.0 Proprietary and Confidential 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.1 2.2 4.1 4.2 4.3 5.1 5.2 5.3 5.4 5.5 6.1 6.2 Table of Contents High-End Headset Guide for RTX725x ................................................................................................................................ 1 1 About This Document ................................................................................................................................................. 5 Audience ........................................................................................................................................................... 5 When Should I Read This Guide ........................................................................................................................ 5 Whats Inside This Guide ................................................................................................................................... 5 Whats Not in This guide ................................................................................................................................... 5 Abbreviations .................................................................................................................................................... 5 References/Related Documentation ................................................................................................................. 6 Document History ............................................................................................................................................. 6 What is new ....................................................................................................................................................... 6 Documentation Feedback ................................................................................................................................. 6 2 Package overview ....................................................................................................................................................... 7 Content .............................................................................................................................................................. 7 Damage inspection ............................................................................................................................................ 7 3 System design ............................................................................................................................................................. 8 3.1 DECT Registration .............................................................................................................................................. 8 Handover to VoIP multicell systems ............................................................................................................. 9 3.2 Bluetooth registration ....................................................................................................................................... 9 4 About the device ....................................................................................................................................................... 10 Type of RTX725x headsets .............................................................................................................................. 10 Features of the RTX725x series ....................................................................................................................... 10 Headsets overview .......................................................................................................................................... 12 Ear cushions ................................................................................................................................................ 13 Physical buttons .......................................................................................................................................... 14 4.4 LED overview ................................................................................................................................................... 15 LED patterns ................................................................................................................................................ 15 LED indication ............................................................................................................................................. 15 4.5 Battery ............................................................................................................................................................. 16 5 Features overview .................................................................................................................................................... 17 Eco mode ......................................................................................................................................................... 17 Auto answer/mute .......................................................................................................................................... 17 BT/DECT call control ........................................................................................................................................ 17 Headset Music control .................................................................................................................................... 17 Summary ......................................................................................................................................................... 18 6 Regulatory compliances ............................................................................................................................................ 20 Safety & Type approvals .................................................................................................................................. 20 Environmental compliances ............................................................................................................................ 21 APPENDIX .......................................................................................................................................................................... 22 RTX725x GUIDE 1.0 Proprietary and Confidential 7 DECT cradle registration ........................................................................................................................................... 22 RTX725x GUIDE 1.0 Proprietary and Confidential 1 About This Document This document describes the configuration, management, operation and maintenance of the RTX725x headset series which are part of the range of the DECT system. For customer specific modes, please refer to specific customer agreements. 1.1 Audience This guide is intended for everyday users. Furthermore, network administrators, IT support and anyone who wishes to gain knowledge on the fundamental features of the RTX725x headset series can also benefit from this material. 1.2 When Should I Read This Guide Read this guide before you install the devices and before setting up the DECT connection. This manual will enable you to set up components in your network to communicate with each other and deploy a fully functionally system. 1.3 Whats Inside This Guide We summarize the contents of this document in the table below:

WHERE IS IT?

CHAPTER 2 CHAPTER 3 CONTENT Package overview System design CHAPTER 4 About the device CHAPTER 5 CHAPTER 6 CHAPTER 7

(APPENDIX) Features overview Regulatory compliances DECT cradle registration 1.4 Whats Not in This guide PURPOSE Presents the package content and handling Gives an overview of how RTX725x communicates in the system Provides information on the device specifications and hardware Introduces the supported features on the headset Presents the adherence to the laws and regulations Illustrates the steps behind the process Since the RTX725x series covers 3 different headsets, one of them (RTX7251) will not be covered in detail in this document. However, in general, it follows the same specification as the RTX7252. More details about the different headsets can be seen in the beginning of the document. Furthermore, the paper is not intended as a comprehensive reference to details and specific steps on how to configure other vendor specific components/devices. For such a reference to vendor specific devices, please contact the respective vendor for documentation. 1.5 Abbreviations For this document, the following abbreviations hold:

DECT:

MWI:

PCBA:

MFB:

BT:

Digital Enhanced Cordless Telecommunications Message Waiting Indicator PCB Assembled Multi-Function Button Bluetooth RTX725x GUIDE 1.0 Proprietary and Confidential 5 | P a g e 1.6 References/Related Documentation PC tool Base guide 1.7 Document History REVISION 1.0 AUTHOR DKO ISSUE DATE 07.05.2020 COMMENTS First release 1.8 What is new What new features have been added. VERSION V1.0 FEATURE First release 1.9 Documentation Feedback We always strive to produce the best and we also value your comments and suggestions about our documentation. If you have any comments about this guide, please enter them through the Feedback link on the RTX website. We will use your feedback to improve the documentation. RTX725x GUIDE 1.0 Proprietary and Confidential 6 | P a g e 2 Package overview Prior to opening, examine the shipping package for evidence of physical damage. If there is proof of mishandling prior to opening, you must report it to the relevant support center of the regional representative or operator. 2.1 Content Make sure all relevant components are available in the package before proceeding to the next step. In principle, every shipped headset unit package/box contains the following items:

1x headset 1x base station (charger) 1x PSU fixed 1x USB C cable 1x 600mAH Li-polymer battery 1x 1-page A5 double side B/W print Customer specific changes may occur. 2.2 Damage inspection The following steps are recommended to be followed for damage inspection:

1. Examine all relevant components for damage 2. Make a defective on arrival - DOA report or RMA to the operator. Do not move the shipping carton until it has been examined by the operator. The operator/regional representative will initiate the necessary procedure to process this RMA. They will guide the network administrator on how to return the damaged package if necessary. If no damage is found, then unwrap all the components and dispose of empty package/carton(s) in accordance with country specific environmental regulations. 3. RTX725x GUIDE 1.0 Proprietary and Confidential 7 | P a g e 3 System design The high-end headsets support the DECT and BT technology to establish connection with other devices. They are used with the RTX7451 DECT base and Desk Phone / PC / Laptop/ mobile phones. The selected microphone is balanced together with the headset filters to reduce the background noise to provide an ultimate understandable and clear speech. On the other hand, the receivers are balanced to the receiver housing and cushion, so the headset will provide the user an excellent stereo experience. The figure below (Fig.1) illustrates the high-level description of the system. It provides the basic understanding of the environment in which the device needs to interact. Both communication possibilities of the RTX725x are presented in the drawing below. Fig.1: System overview 3.1 DECT Registration The headset is registered to the base (RTX7451) by mounting the headset in the cradle (Fig.2). The registration status can be seen on the base display and a voice prompt can be activated via the PC tool to inform the end-user. The headset can also register to the RTX374x DECT dongle by placing both headset and dongle in registration mode. On the headset, this is done by holding the DECT button for 2 seconds. For further details on the registration process, please refer to Appendix. Fig.2 DECT registration and charging 8 | P a g e RTX725x GUIDE 1.0 Proprietary and Confidential Handover to VoIP multicell systems The RTX725x headset and RTX7451 base together can integrate into VoIP multicell and dual cell systems. The headset base will register on behalf of itself and the headset. The two registrations are independent but will be linked logically as one unit on the VoIP system. The purpose of this integration is to hand over the users calls to the VoIP system for the user to be flexible in terms of location. Fig.3 Call Handover 3.2 Bluetooth registration The headset is registered to a Bluetooth device by holding the BT button for 2 seconds. This will enable pairing mode for the headset which then allows it to be discovered by other Bluetooth devices. The RTX725x can store up to 4 paired BT devices information and remain connected to 2 of them at the same time. In case of reaching the limit and pairing a new device after the 4 existing ones, the oldest device information will be overwritten by the new agent. Major mobile platforms are supported, such as iOS and Android. Fig.4 BT connection RTX725x GUIDE 1.0 Proprietary and Confidential 9 | P a g e 4 About the device The RTX725x series are wireless DECT+BT headsets. As mentioned before, the headset connects to the DECT base, which acts as a charger for the headset, via the DECT wireless technology. It can also connect via Bluetooth to supported devices such as mobile phones and Bluetooth compatible desk phones. A Busy-light indicator on the headband is used to indicate that the user is busy. The headset also features Environmental Noise Cancellation (ENC) to suppress unwanted environmental noise for the microphone input and Active Noise Cancellation (ANC) to suppress the noise towards the user. The headset offers DSP assisted echo cancelling. The length of the headband is adjustable to suit the head-shape of different users and the tilting angle of the boom can be adjusted to fit the position of the mouth of different people. The DECT base / charger connects to the PC/laptop. It can access Skype for Business and a defined range of soft call clients from external vendors, as well as a defined range of desk phones via EHS interface. Call control can be managed via the base, attached desk phones, soft call clients on the PC or via the buttons on the left earcup of the headset. A conferencing feature allows up to 4 headsets to connect to the same base users may be added / removed from the conferencing call on the fly. The primary application of the RTX725x is within call centers and office environments allowing the user to access the internet/VoIP calls and music playback via the PC/BT. 4.1 Type of RTX725x headsets The headset auto-configures the DECT setup when connecting to the base, thus no country specific variants exist. As mentioned earlier, the RTX725x series covers 3 different headsets:

Model RTX7251 RTX7252 RTX7254 Product DECT Mono high-end Headset DECT Stereo High-end Headset DECT Stereo High-end Headset ANC Country Variant World wide

(Taiwan, EMEA, Brazil & Uruguay, LATAM, Argentina, Chile, USA, Canada) World wide

(Taiwan, EMEA, Brazil & Uruguay, LATAM, Argentina, Chile, USA, Canada) World wide

(Taiwan, EMEA, Brazil & Uruguay, LATAM, Argentina, Chile, USA, Canada) 4.2 Features of the RTX725x series The features of the above-mentioned headsets are summarized and listed in the table below:

RTX7251 Mono RTX7252 Stereo RTX7254 Stereo ANC Main headset features Fold flat design Ear cup Ear pads material Ear pads attachment Over the ear On ear RTX725x GUIDE 1.0 Proprietary and Confidential No Yes Yes, 2-way Fabric and PU Leather Detachable Yes Yes Yes Yes 10 | P a g e Ear cup movement Flexible boom Boom movement Headband material Headband rachet Ratchet marking indication (on head side) Busy light Proximity sensor

(Auto Hook off) Noise cancellation ENC ANC Echo Cancelling No. of microphones No. of receivers No. of buttons Scroll wheel for volume control Support for Voice Prompts Voice prompt language English Call control Vol+

Vol-

MFB DECT Conference calls

(supervisor) Bluetooth Adaptive Power Control (DECT) Handover to VoIP multicell systems Firmware update support Call status LED Narrow band Audio Wide band Audio Super wide band Acoustic shock protection UCB C Connector RTX725x GUIDE 1.0 Proprietary and Confidential No 2 1 5 Yes DSP assisted Yes DSP assisted Yes DSP assisted 6 2 6 2-axis Bendable 270 rotation Plastic and silicone 30mm2mm Integrated on boom arm multi-color LED No Yes No 2 2 6 Yes Yes Configurable via PC Tool Included Scroll wheel up Scroll wheel down Answer/end call, etc Yes 4 users Yes, BT4.2 Yes Yes Via PC Tool G726, BV16 CELT, G.722, BV32 Yes Yes Yes Integrated on boom arm multi-color LED 11 | P a g e 4.3 Headsets overview The following section aims to give an overview of the headsets and the available buttons. The following drawings illustrate the dimensions of the RTX725x series headsets. Fig.5: Dimensions of RTX7251 Fig.6: Dimensions of RTX7252 Fig.7: Dimensions of RTX7254 12 | P a g e RTX725x GUIDE 1.0 Proprietary and Confidential The images below represent the styling of all 3 headsets from the RTX725x series. By default, the color is grey, and the devices have removable ear cushions. Fig.9: Styling of RTX7251 Fig.8: Styling of RTX7252 and RTX7254 Ear cushions The cushions of the headsets are removable and replaceable. There are two types of ear cushions on-ear and over-

the-ear (Fig.7 Ear cushions). The only headset that supports the two types is the RTX7254. A sensor in the headset detects which type of cushion is used and adapts the audio tuning accordingly in order to get the optimal noise reduction. The other two devices (RTX7251 and RTX7252) only support the on-ear cushion solution. Fig.10: Ear cushions 13 | P a g e RTX725x GUIDE 1.0 Proprietary and Confidential Physical buttons The headset is operated using the buttons on the earcup with boom arm. The ANC button is located on the opposite earcup as ANC is not available for Mono headsets. Fig.11: Double Bottom view Fig.12: One-sided view Fig.13: Back side view 14 | P a g e RTX725x GUIDE 1.0 Proprietary and Confidential The following table represents the functions of the buttons seen on the figures above Functions Power the headset on and off Increase volume Decrease volume Play/Pause music Skip to next track Answer call End call Reject call Trigger AI voice assistant Toggle busy Toggle mute Announce battery level Enter DECT pairing mode Reset settings Toggle Bluetooth Enter Bluetooth pairing mode Toggle ANC Input Power slider Scroll wheel with an integrated key Multi-Function Button Mute key DECT key BT key ANC key 4.4 LED overview LED patterns The headset has a single tricolor LED on the tip of the boom-arm, which is a combination of 3 LEDs red, green and blue. All visual indications are disabled if eco mode is enabled. The LED supports 3 different kinds of patterns. The definitions of each pattern can be seen in the table below:

LED pattern Blink Breathing Alternating Definition ON-OFF Onecolorthatslowly becomes brighter until it reaches full brightness and then dimmers until fully dimmed.It is a repeated cycle. Alternating between two colors LED indication The table below presents the LED indication depending on the status of the headset. Function System Status LED color Pattern Reset setting started Purple Blink 3 times Bluetooth registration Registration, In progress Blue, red Registration, Success Green Registration, Failed Red Alternating Blink 3 times Blink 3 times 15 | P a g e RTX725x GUIDE 1.0 Proprietary and Confidential DECT registration Battery status Registration, In progress Blue, red Registration, Success Registration, Failed No battery Fully charged Charging Low Green Red Cyan Green Green Red Red Alternating Blink 3 times Blink 3 times Blink ON Breathing Breathing ON Busy mode Busy enabled or call active 4.5 Battery The headsets use 600mAH Li-polymer battery, which is easily replaceable after removing the battery lid, as illustrated on the image below. Fig.14: Battery lid removed The RTX725x can be charged in 2 ways. One of the options is placing the headset in the cradle of the base, which displays the charging status. Another way to charge the device can be with the use of a USB cable, where the status will be shown on the boom-arm LED. For more details about the battery LED indications, please refer to the previous section 4.4.2 LED indication. The battery performance can be seen in the summary table of features in section 5.5. Summary. RTX725x GUIDE 1.0 Proprietary and Confidential 16 | P a g e 5 Features overview This section aims to introduce you to the available features of the headset series RTX725x. Some of the features will be briefly described through the sections below, whereas the main highlights will be presented via a table with function descriptions. 5.1 Eco mode RTX725x headsets support ECO mode which increases the talk time to 12 hours. This is done by limiting some of the features, such as power consumption of the LED indication and audio codec selection. This means that the BV16 narrowband codec is used during ECO mode and the LED is be dimmed or turned off to save power. 5.2 Auto answer/mute The RTX725x series uses a proximity sensor to detect when the user is wearing or removing the headset. This means that the sensor is used to trigger two events:

Auto answer of an incoming call when user places the headset on the head Auto mute/unmute a call when user removes/places back the headset on the head These two settings can be managed in the Device settings of the PC setup tool software. The user should bear in mind that even if these settings are enabled, the users actions will dominate. This means, for example, if the user enables the auto mute feature and then mutes the call while the headset is on their head, the call will remain muted even if the user removes and places back the headset on the head. The following table illustrates the headset key functionalities and the related call control events when pressed. Double Press Long Press Hold/Resume call Reject call 5.3 BT/DECT call control Key button Multi-Function Volume Roll Up Volume Roll Down Mute BT Press Accept/End call Increase the volume Decrease the volume Mute/Un-mute Toggle BT on/off The RTX725x supports 2 active calls, meaning that the 3rd incoming call will be rejected or ignored. If during a call the user receives an incoming call, the call can be rejected by double pressing the Multi-Function key or accepted by long pressing the same key. The long press will answer the incoming call and put on hold the current one. BT pairing mode 5.4 Headset Music control The user can control the music features by pressing the available keys on the headset. Volume control is supported in smartphones with operating system older than 6.0 for Android and 5.0 for iOS. The volume levels will be synchronized between the headsets and the audio device. The keys will trigger the following events presented in the table below:

Double Press Long Press Skip to next track

17 | P a g e BT pairing mode Key button Mute Press Play/Pause music Volume Roll Up Volume Roll Down Increase the volume Decrease the volume BT Toggle BT on/off RTX725x GUIDE 1.0 Proprietary and Confidential

The table below presents a summary of the features available in the headsets. 5.5 Summary Input DECT frequency bands:

Narrowband Audio:

Wideband Audio (HD):

Music LED Indicator Status LED Visibility Hardware Features Battery type Battery capacity Microphones Headset interface Charging terminals Operating conditions Battery Performance Talk time DECT Talk time BT Standby time DECT only:

Standby time DECT+BT:

Charge time (0% - 90%) Quick charge Charge stop temperature Audio Features Earpiece volume Coverage warning Language Supported:

Call features Call waiting Hold / Retrieve No. of simultaneous calls Call Conference Call Swap DECT Output Power Sensitivity Antenna RTX725x GUIDE 1.0 Proprietary and Confidential Functions 1880 1895 MHz (Taiwan) 1880 1900 MHz (EMEA) 1910 1920 MHz (Brazil & Uruguay) 1910 1930 MHz (LATAM, Argentina, Chile) 1920 1930 MHz (USA, Canada) G.726, BV16 G.722, BV32 128 kbit/s CELT Tri color Mic boom tip Lithium Polymer, replaceable 600 mAh 2 for talk (ENC) and 4 for ANC USB to connect to the RTX7451 base Using USB

-0 C to 45C Up to 20 hours Up to 10 hours Up to 100 hours Up to TBD hours 3 hours 25% in 30 minutes Low temperature stop charge: 5C High temperature stop charger: 40C See volume table On/Off English (Voice prompts) Yes Yes 2, only one on hold Yes Yes 250 mW 140 mW (Uruguay, Canada, US, Malaysia, Jordan) 22 dBm (Chile, Australia)

-92 dBm 2 for fast antenna diversity 18 | P a g e Range (max) Security Standard DECT interface Handover to VoIP multicell systems Software Update Downloadable Air-interface Bluetooth No. of pairings BT Version Frequency Sensitivity Simultaneous connections Profiles Output power Range Antenna A2DP

- Hsp

- HFP

- DIP

- AVRCP SBC Codec

- mSBC

- CVSD Audio Codec Class of device Bluetooth device address Bluetooth device name Encryption Pairing mode Automatic connect Others HAC compliant RTX725x GUIDE 1.0 Proprietary and Confidential 200m outdoor Class C Yes Yes Yes Yes 4 4.2 Classic 2401 MHz 2480 MHz Better than -92 dBm @ DH1, measured at antenna Class 2, 2,5mW (4dBm) 10 meters in free line of sight measured outsight The antenna performance should be designed to have a return loss of < -5dB in the relevant frequency band 2 1.2 Advanced Audio Distribution Profile 1.2 Headset Profile 1.6 Handsfree Profile 1.3 Device ID Profile 1.4 Audio/Video Remote Control Profile For stereo streaming of music For wideband audio For narrowband audio BV16 G.726 BV32 G.722 CELT48 0x200404 Headset device 0x200418 Headphones The address is stored in non-volatile memory The product shall use the name XXXXXXXX *

Default 128-bit encryption Discoverable only by user request and limited time 1 minute An already paired Bluetooth device will automatically connect to the headset. Yes 19 | P a g e 6 Regulatory compliances 6.1 Safety & Type approvals The regulatory compliance and measurements reports required are:

Approval Safety Safety Safety FCC FCC FCC FCC FCC IC IC IC IC IC IC CE CE CE CE CE CE CE RCM RCM RCM RCM RCM RCM Standard GENERAL SAFETY CB IEC62368, EN62368, IEC60950, EN60950 Including the country deviation to US/CA, AU/NZ and EU UL62368, and NRTL for US and CA CB Scheme Certificate US FCC Part 15B FCC Part 15D FCC Part 15.247 FCC SAR evaluation FCC ID CANADA ICES-003 Issue 6, 2016 IC RSS-213 Issue 3,March 2015 IC RSS-102 issue 5 SAR evaluation IC RSS-247 IC REL Cert and registration ISED ID EUROPEAN EN55032:2015 EMC-EMI&EMS EN55024:2010 EN55035 EN62479:2010 EN301489-1 V2.2.0 (2017-03) EN301489-6 V2.2.0 (2017-03) EN301489-17 V3.2.0 (2017-03) IEC61000-4-2 Level 3 EN61000- 4-3 Level 3 EN301406V2.2.2(2016-09) EN300328V2.1.1(2016-11) SAR-EN62209-1:2006/EN62209-2:2010 ;

EN50360 :2001+A1:2012 EN 50566:2013/AC:2014 AOC certificate AUSTRALIA/NZ AS/NZS CISPR 32:2015 EMC-AS/NZS CISPR 22:2009+A1:2010 RF-AS/NZS 4268:2017 SAR-AS/NZS 2772.1; AS/NZS 2772.2:2011 Acoustic AS/CA S004 HAC AS/ACIF S040 RTX725x GUIDE 1.0 Proprietary and Confidential 20 | P a g e 6.2 Environmental compliances RoHS Per Directive 2011/65/EU on the Restriction of the use of certain Hazardous Substances in Electrical and Electronic Equipment REACH Per Directive 1907/2006 on Registration, Evaluation and Authorization of Chemicals WEEE Per Directive 2012/19/EU on Waste Electrical and Electronic Equipment

(RTX will add waste bin information on product labels). Packaging: EU Directive 97/129/EC establishing the identification system for packaging materials pursuant to European Parliament and Council Directive 94/62/EC on packaging and packaging waste RTX725x GUIDE 1.0 Proprietary and Confidential 21 | P a g e APPENDIX 7 DECT cradle registration The following steps serve as a guideline for the process of registering the RTX725x headsets to the RTX745x base. Registration mode is enabled by inserting the headset into the base cradle. The headset can be registered as both primary and secondary. When the headset is locked as secondary on another RTX745x base or on an RTX374x FP dongle, the user may return the headset to use its primary state by inserting the headset into the cradle of the primary base. Step 1 Step 2 Step 3 Insert the headset into the base cradle The headset identifies itself to the base The base decides if the headset can register a. If the headset is allowed to register it plays back the Registering voice prompt once i. The headset starts the Registration, in progress LED pattern ii. The base displays a visible notification that cradle registration is initiated iii. The headset plays back the Registration succeeded voice prompt once iv. The headset displays the Registration, success LED pattern v. The base displays a visible notification that cradle registration succeeded b. If the headset is not allowed to register it plays back the Registration failed voice prompt once i. The headset displays the Registration, failure LED pattern ii. The base displays a visible notification that cradle registration failed RTX725x GUIDE 1.0 Proprietary and Confidential 22 | P a g e 8 Declaration of compliance 8.1 FCC warning This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

Reorient or relocate the receiving antenna. Increase the separation between the equipment and receiver. Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. Consult the dealer or an experienced radio/TV technician for help. Changes or modifications to this equipment not expressly approved by the party responsible for compliance could void the users authority to operate the equipment. This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. SAR tests are conducted using standard operating positions accepted by the FCC with device transmitting at its highest certifed power level in all tested frequency bands, although the SAR is determined at the highest certified power level, the actual SAR level of the device while operating can be well below the maximum value. Before a new model device is an available for sale to the public, it must be tested and certifed to the FCC that it does not exceed the exposure limit established by the FCC, tests for each device are performed in positions and locations as required by the FCC. For body worn operation, this model device has been tested and meets the FCC RF exposure guidelines when used with an accessory designated for this product or when used with an accessory that contains no metal. For Handset For Base This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator& your body. This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter located or operating in conjunction with any other antenna or transmitter. 8.2 ISEDC Warning This device contains licence-exempt transmitter(s)/receiver(s) that comply with Innovation, Science and Economic Development Canadas licence-exempt RSS(s). Operation is subject to the following two conditions:

1. This device may not cause interference. 2. This device must accept any interference, including interference that may cause undesired operation of the device. 23 | P a g e RTX725x GUIDE 1.0 Proprietary and Confidential Cet appareil est compatible avec la licence de lInnovation, la Science et le dveloppement conomique du Canada lexemption des normes RSS. Le fonctionnement est sujet aux deux (2) conditions suivantes :

(1) Cet appareil peut ne pas causer de linterfrence, et

(2) Cet appareil doit accepter linterfrence, incluant de linterfrence qui peut causer un mauvais fonctionnement de cet appareil. For Handset SAR tests are conducted using standard operating positions accepted by the ISEDC with device transmitting at its highest certified power level in all tested frequency bands, although the SAR is determined at the highest certified power level, the actual SAR level of the device while operating can be well below the maximum value. Before a new model device is an available for sale to the public, it must be tested and certified to the ISEDC that it does not exceed the exposure limit established by the ISEDC, tests for each device are performed in positions and locations as required by the ISEDC. For body worn operation, this model device has been tested and meets the ISEDC RF exposure guidelines when used with an accessory designated for this product or when used with an accessory that contains no metal For Base This equipment complies with ISEDC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator& your body. This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter located or operating in conjunction with any other antenna or transmitter. Pour le combin Les tests SAR sont faits en utilisant les normes de positions dopration acceptes par lISEDC avec les appareils mettant les plus hauts niveaux de puissance certifis sur toutes les bandes de frquences, mme si le SAR est dtermin dtre du plus haut niveau de puissance certifi, le niveau SAR actuel de lappareil peut tre sous la valeur maximale de fonctionnement. Avant quun nouveau modle dappareil ne soit disponible pour la vente au public, celui-ci doit tre soumis des tests de certification par lISEDC lesquels nexcdent aucunement la limite dexposition issue par lISEDC, lesquels sont des tests effectus sur chaque appareil dans des positions et endroits requis par lISEDC. Pour lusure de construction de ce modle dappareil, celui-ci a t test et rencontre les lignes directrices mises par lISEDC RF pour lexposition, lorsquil est utilis avec un accessoire conu pour ce produit ou utilis avec un accessoire qui ne contient aucun mtal. Pour la base Cet quipement est conforme avec les limites dexposition la radiation de lISEDC mises dans un environnement contrl. Cet quipement devrait tre install et fonctionnel avec un minimum de distance entre le radiateur et votre corps dau moins 20 cm. Ce transmetteur ne doit pas tre co-situ prs dune autre antenne ou en conjonction avec un autre transmetteur. This Class B digital apparatus complies with Canadian ICES-003. Cet appareille numrique de classe B est conforme aux normes canadiennes ICES-003. RTX725x GUIDE 1.0 Proprietary and Confidential 24 | P a g e

RoHS HAC 2D Barcode Model: RTX7254 FCC ID: T7HHT7254 IC:4979B-HT7254 3.8V 600mAh S/N: YYWWSSSSSS Made in China 7

. 9 1 29.4 H=5.5mm H=7mm H=5mm Headset Model: RTX7251, RTX7252, RTX7254 SIZE : W29.4mm x H19.7mm Material: PET Positioning: Stick inside the battery compartment Color: Black text on white background Barcode format: 2D Barcode (Data Matrix) Barcode size: 4.7mm X 4.7mmMin Barcode contain information:

1.Serial number 2.IPEI code 3.BT MAC address Information show horizontally after scanned:

YYWWSSSSSS ; 0EEEEZZZZZ ; MMMMMMMMMMMM Location Serial number format (YYWWSSSSSS):

YY: Year of manufacturing (e.g. 10=2010) WW: Week of manufacturing SSSSSS: Progressive serial number. Serial starting number is 000001, the serial number will only reset to 000001 if under the following condition:

a) The start of new PO production lot, plus the production week WW increment to a new week. Otherwise the serial number will continuous the previous lot of production. IPEI format:

0EEEEZZZZZ IPEI code in text (HEX format) 0: this is a fix digit EEEE: EMC code ZZZZZ: start from 00001, this five digits cannot be all zero, thats mean 00000 is not allowed BT MAC format:

MMMMMMMMMMMM :BT MAC address in text

(The SN, IPEI code & BT MAC address on headset must be matched with the one on packing box) RTX725x HS product Label 50004892 (RTX7254) REV. A 3-June-2020

RTX HONG KONG LTD Agent Authorization Company: RTX HONG KONG LTD Address: 8/F Corporation Square 8 Lam Lok Street, Kowloon Bay, Kowloon, Hong Kong Product Name: Wireless Mono Headset,Wireless Stereo Headset,Wireless Stereo ANC Headset Model Number(s): RTX7251,RTX7252,RTX7254 Product Description: Wireless Headset with DECT function We authorize MiCOM Labs Inc., 575 Boulder Court, Pleasanton, California 94566, USA, to act on our behalf on all matters concerning the certification of above named equipment. We declare that MiCOM Labs Inc. is allowed to forward all information related to the approval and certification of equipment to the regulatory agencies as required and to discuss any issues concerning the approval application. Any and all acts carried out by MiCOM Labs on our behalf shall have the same effect as acts of our own. Signature:

Date: 2023.01.09 Name:

Erik Pedersen Title:

Engineering Director Company: RTX HONG KONG LTD

Differences Description We RTX HONG KONG LTD state:

Product Model Name Wireless Mono Headset Wireless Stereo Headset Wireless Stereo ANC Headset RTX7251 RTX7252 RTX7254 Trade Name: RTX FCC ID: T7HHT7254 IC: 4979B-HT7254 The Model Differences show as below table:

RTX 7251 is mono headset, RTX7252 is stereo headset, RTX7254 is stereo headset with ANC function. They share the same main PCB layout. Signatory Date 2022-12-28 Signature:

Name: Erik Pedersen Title: Engineering Director Company: RTX HONG KONG LTD Address: 8/F Corporation Square 8 Lam Lok Street, Kowloon Bay, Kowloon, Hong Kong

RTX HONG KONG LTD February 15, 2023 Federal Communications Commission Equipment Authorization Division 7435 Oakland Mills Road Columbia, MD 21046 USA Attn: OET Dept. Ref: FCC Class II Permissive change for FCC ID: T7HHT7254 Applicant: RTX HONG KONG LTD Dear Examiner, This is to request a Class II Permissive change for FCC ID: T7HHT7254 originally granted on 10/28/2020 (date). The change under this application is to 1.BT antenna change from PCB type antenna to chip antenna, filter for BT change from IC type to discrete component. The BT test data and standard has been updated. OLD NEW FCC Class II PC request letter Rev1.1.docx 2.DECT antenna change: Antenna position and material change, SAR and radiation spurious have been retested. OLD NEW 3.Update, applicant and manufacturer address. I attest that the certified device will not be capable of ad-hoc mode operation outside of the grant conditions. Sincerely, Name: Erik Pedersen Date: 2023.02.14 Title: Engineering Director Signature of applicant:

FCC Class II PC request letter Rev1.1.docx

RTX HONG KONG LTD Covered Equipment Certification Attestation Letter 3/13/2023 MiCOM Labs Inc. 575 Boulder Court, Pleasanton, California 94566, USA ATTN.: Reviewing Engineer FCC ID: T7HHT7254 RTX HONG KONG LTD (the applicant) certifies that the equipment for which authorization is sought is not covered equipment prohibited from receiving an equipment authorization pursuant to section 2.903 of the FCC rules. Note: If the equipment for which the applicant seeks authorization is produced by any of the entities identified on the current Covered List, the applicant should include an explanation on why the equipment is not covered equipment. RTX HONG KONG LTD (the applicant) certifies that, as of the date of the filing of the application, the applicant is not identified on the Covered List as an entity producing covered equipment. Signed:

Printed name: Erik Pedersen Title: Engineering Director Company Name: RTX HONG KONG LTD Date: 3/13/2023

RTX HONG KONG LTD Office of Engineering Technology Federal Communications Commission 7435 Oakland Mills Road Columbia, MD 21046 USA Subject; Request for Confidentiality FCC ID: T7HHT7254 To Whom It May Concern, Date: 2023.01.09 Pursuant to the provisions of the Commissions rules Title 47 Sections 0.457 and 0.459, we are requesting the Commission to withhold the following attachment(s) as confidential documents from public disclosure indefinitely. These documents contain detailed system and equipment descriptions and are considered as proprietary information in operation of the equipment. The public disclosure of these documents might be harmful to our company and would give competitors an unfair advantage in the market. Schematic Diagram Block Diagram Operational Description Tune-up Procedure Part List Software Security Requirements For U-NII Devices In additional to above mentioned documents, in order to comply with the marketing regulations in Title 47 CFR 2.803 and the importation rules in Title 47 CFR 2.1204, while ensuring that business sensitive information remains confidential until the actual marketing of newly authorized devices, we request Short Term Confidentiality of the following attachment(s);

External Photos Test Setup Photos Internal Photos User Manual For 45 days, pursuant to Public Notice DA 04-1705. RTX HONG KONG LTD OR For 180 days pursuant to KDB 726920 D01. It is our understanding that all measurement test reports, FCC ID label format and correspondence during the certification review process cannot be granted as confidential documents and this information will be available for public review once the grant of equipment authorization is issued. Sincerely, Signature:

Name: Erik Pedersen Title: Engineering Director

RTX HONG KONG LTD 2020.10.04 MET Laboratories, Inc. 914 West Patapsco Avenue Baltimore, MD 21230 RE: LETTER OF AGENT AUTHORIZATION To Whom It May Concern:

We, RTX HONG KONG LTD hereby authorize (Shenzhen STS Test Services Co., Ltd.) to act on our behalf in all matters relating to application for equipment authorization, including the signing of all documents relating to these matters. We also hereby certify that no party to the application authorized hereunder is subject to the denial of benefits, including FCC benefits, pursuant to Section 5301 of the Anti-Drug Abuse Act of 1988, 21 U.S.C.853(a). This agreement expires one year from the current date. Sincerely, Name: Ted Chong Signature:

TCBJ FORM-4 Issued by: TCB Administrator Revision 6 12/06/10

Differences Description We RTX HONG KONG LTD state:

Wireless Mono Headset Wireless Stereo Headset Wireless Stereo ANC Headset RTX7251 RTX7252 RTX7254 Product Model Name Trade Name: RTX FCC ID: T7HHT7254 IC: 4979B-HT7254 The Model Differences show as below table:

RTX 7251 is mono headset, RTX7252 is stereo headset, RTX7254 is stereo headset with ANC function. They share the same main PCB layout. Signatory Date 2020-10-04 Signature:

Name: Ted Chong Title: Engineering Manager Company: RTX HONG KONG LTD Address: 8TH FL CORPORATION SQUARE, 8 LAM LOK ST., KOWLOON BAY, HK.

RTX HONG KONG LTD 2020.10.04 MET Laboratories, Inc. 914 West Patapsco Avenue Baltimore, MD 21230 RE: CONFIDENTIALITY REQUEST FOR (Wireless Mono Headset,Wireless Stereo Headset,Wireless Stereo ANC Headset / RTX7251,RTX7252,RTX7254 /FCC ID: T7HHT7254) To Whom It May Concern:

This letter serves as an official request for confidentiality under sections 0.457 and 0.459 of CFR 47. We have requested that the These materials contain trade secrets and proprietary information and are not customarily released to the public. The public disclosure of this information might be harmful to the company and provide unjustified benefits to our competitors. required to be submitted with this application be permanently withheld from public review. Please contact me if there is any information you may need. Sincerely, Name: Ted Chong Signature:

Schematics Block diagram Operation description BOM Tune Up Procedure TCBJ FORM-4 Issued by: TCB Administrator Revision 6 12/06/10