2AYZ9-KZTWSTWS Bluetooth earphone

Dongguan Yuan Ze Acoustics Technology., Ltd Mar.02, 2021 Office of Engineering Technology Federal Communications Commission 7435 Oakland Mills Road Columbia, MD 21046 USA Subject: Explanation of differences between product types FCC ID : 2AYZ9-KZTWS Model Number: SA08, Z1, S2, Z1 PRO, SK1, SKS, Z3, VX10, S1A, S1 PRO To Whom It May Concern: We, The Dongguan Yuan Ze Acoustics Technology., Ltd hereby declare that the models are identical except the model name. Except for the different above, no other modification is performed. Sincerely, Signature: Dongguan Yuan Ze Acoustics Technology.,Ltd Contact person: Yalin Chen

Dongguan Yuan Ze Acoustics Technology., Ltd Agent Authorization Company: Dongguan Yuan Ze Acoustics Technology., Ltd Address: 2nd Floor, Building A, 26 Hantang Street, Qiantou Community Dongcheng Street, Dongguan City, Guangdong Province, China Product Name: TWS Bluetooth earphone Model Number(s): SA08, Z1, S2, Z1 PRO, SK1, SKS, Z3, VX10, S1A, S1 PRO Product Description: TWS Bluetooth earphone 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: 2021-03-02 Name: Yalin Chen Company: Dongguan Yuan Ze Acoustics Technology.,Ltd

Dongguan Yuan Ze Acoustics Technology., Ltd Office of Engineering Technology Federal Communications Commission 7435 Oakland Mills Road Columbia, MD 21046 USA Date: 2021-03-01 Subject; Request for Confidentiality FCC ID: 2AYZ9-KZTWS To Whom It May Concern, Pursuant to the provisions of the Commission’s 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 Parts List Operational Description Tune-up Procedure 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. 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 Dongguan Yuan Ze Acoustics Technology.,Ltd Contact person: Yalin Chen

External Photos WHOLE VIEW OF EUT TOP VIEW OF EUT BOTTOM VIEW OF EUT FRONT VIEW OF EUT BACK VIEW OF EUT LEFT VIEW OF EUT RIGHT VIEW OF EUT Left VIEW OF EUT(PORT) Right VIEW OF EUT(PORT)

FCC ID Label Location The product does not have enough space to place the label, and FCC ID label is reflected in the user manual and package, as below:

Internal Photos Left OPEN VIEW OF EUT VIEW OF BATTERY INTERNAL VIEW OF EUT-1 INTERNAL VIEW OF EUT-2 BT Antenna INTERNAL VIEW OF EUT-3 INTERNAL VIEW OF EUT-4 Right OPEN VIEW OF EUT VIEW OF BATTERY INTERNAL VIEW OF EUT-1 INTERNAL VIEW OF EUT-2 BT Antenna INTERNAL VIEW OF EUT-3 INTERNAL VIEW OF EUT-4

RF EXPOSURE EVALUATION 1. PRODUCT INFORMATION Product Description TWS Bluetooth earphone Model Name SA08, Z1, S2, Z1 PRO, SK1, SKS, Z3, VX10, S1A, S1 PRO FCC ID 2AYZ9-KZTWS 2. EVALUATION METHOD According to 447498 D01 General RF Exposure Guidance v06 The 1-g and 10-g SAR test exclusion thresholds for 100 MHz to 6 GHz at test separation distances ≤ 50 mm are determined by: [(max. power of channel, including tune-up tolerance, mW)/(min. test separation distance, mm)] ·[√f(GHz)] ≤ 3.0 for 1-g SAR and ≤ 7.5 for 10-g extremity SAR. Where f(GHz) is the RF channel transmit frequency in GHz Power and distance are rounded to the nearest mW and mm before calculation 3. CALCULATION BR&EDR P t =4.027dBm=2.53mW The value of the Maximum output power P t is referred to the test report of the CFR47 §15.247. The result for RF exposure evaluation SAR=(2.53mW /5mm) .[√2.402GHz)]=0.78<3.0 for 1-g SAR and ≤ 7.5 for 10-g extremity SAR. 4. CONCLUSION The SAR evaluation is not required.

Report No.: AGC06023210201FE03 Page 45 of 83 8-DPSK MODULATION IN HIGH CHANNEL Hopping off Hopping on Report No.: AGC06023210201FE03 Page 46 of 83 10. RADIATED EMISSION 10.1. MEASUREMENT PROCEDURE 1. The EUT was placed on the top of the turntable 0.8 or 1.5 meter above ground. The phase center of the receiving antenna mounted on the top of a height-variable antenna tower was placed 3 meters far away from the turntable. 2. Power on the EUT and all the supporting units. The turntable was rotated by 360 degrees to determine the position of the highest radiation. 3. The height of the broadband receiving antenna was varied between one meter and four meters above ground to find the maximum emissions field strength of both horizontal and vertical polarization. 4. For each suspected emission, the antenna tower was scan (from 1 M to 4 M) and then the turntable was rotated (from 0 degree to 360 degrees) to find the maximum reading. 5. Set the test-receiver system to Peak or CISPR quasi-peak Detect Function with specified bandwidth under Maximum Hold Mode. 6. For emissions above 1GHz, use 1MHz RBW and 3MHz VBW for peak reading. Place the measurement antenna away from each area of the EUT determined to be a source of emissions at the specified measurement distance, while keeping the measurement antenna aimed at the source of emissions at each frequency of significant emissions, with polarization oriented for maximum response. The measurement antenna may have to be higher or lower than the EUT, depending on the radiation pattern of the emission and staying aimed at the emission source for receiving the maximum signal. The final measurement antenna elevation shall be that which maximizes the emissions. The measurement antenna elevation for maximum emissions shall be restricted to a range of heights of from 1 m to 4 m above the ground or reference ground plane. 7. When the radiated emissions limits are expressed in terms of the average value of the emissions, and pulsed operation is employed, the measurement field strength shall be determined by averaging over one complete pulse train, including blanking intervals, as long as the pulse train does not exceed 0.1 seconds. As an alternative (provided the transmitter operates for longer than 0.1 seconds) or in cases where the pulse train exceeds 0.1 seconds, the measured field strength shall be determined from the average absolute voltage during a 0.1 second interval during which the field strength is at its maximum values. 8.If the emissions level of the EUT in peak mode was 3 dB lower than the average limit specified, then testing will be stopped and peak values of EUT will be reported, otherwise, the emissions which do not have 3 dB margin will be repeated one by one using the quasi-peak method for below 1GHz. 9. For testing above 1GHz, the emissions level of the EUT in peak mode was lower than average limit (that means the emissions level in peak mode also complies with the limit in average mode), then testing will be stopped and peak values of EUT will be reported, otherwise, the emissions will be measured in average mode again and reported. 10. In case the emission is lower than 30MHz, loop antenna has to be used for measurement and the recorded data should be QP measured by receiver. High - Low scan is not required in this case. Report No.: AGC06023210201FE03 Page 47 of 83 The following table is the setting of spectrum analyzer and receiver. Spectrum Parameter Setting Start ~Stop Frequency 9KHz~150KHz/RB 200Hz for QP Start ~Stop Frequency 150KHz~30MHz/RB 9KHz for QP Start ~Stop Frequency 30MHz~1000MHz/RB 120KHz for QP Start ~Stop Frequency 1GHz~26.5GHz 1MHz/3MHz for Peak, 1MHz/3MHz for Average Receiver Parameter Setting Start ~Stop Frequency 9KHz~150KHz/RB 200Hz for QP Start ~Stop Frequency 150KHz~30MHz/RB 9KHz for QP Start ~Stop Frequency 30MHz~1000MHz/RB 120KHz for QP Report No.: AGC06023210201FE03 Page 48 of 83 10.2. TEST SETUP Radiated Emission Test-Setup Frequency Below 30MHz RADIATED EMISSION TEST SETUP 30MHz-1000MHz RADIATED EMISSION TEST SETUP ABOVE 1000MHz Report No.: AGC06023210201FE03 Page 49 of 83 10.3. LIMITS AND MEASUREMENT RESULT 15.209 Limit in the below table has to be followed Frequencies (MHz) Field Strength (microvolts/meter) Measurement Distance (meters) 0.009~0.490 2400/F(kHz) 300 0.490~1.705 24000/F(kHz) 30 1.705~30.0 30 30 30~88 100 3 88~216 150 3 216~960 200 3 Above 960 500 3 Note: All modes were tested for restricted band radiated emission, the test records reported below are the worst result compared to other modes. 10.4. TEST RESULT RADIATED EMISSION BELOW 30MHz The amplitude of spurious emissions from 9kHz to 30MHz which are attenuated more than 20 dB below the permissible value need not be reported. Report No.: AGC06023210201FE03 Page 50 of 83 RADIATED EMISSION BELOW 1GHz EUT TWS Bluetooth earphone Model Name SA08 Temperature 25°C Relative Humidity 55.4% Pressure 960hPa Test Voltage Normal Voltage Test Mode Mode 7 Antenna Horizontal NO. Freq. [MHz] Level [dBμV/m] Factor [dB] Limit [dBμV/m] Margin [dB] Height [cm] Angle [°] Polarity 1 43.5800 16.72 11.84 40.00 23.28 100 130 Horizontal 2 68.8000 14.54 9.43 40.00 25.46 100 360 Horizontal 3 133.7900 20.93 14.42 43.50 22.57 100 220 Horizontal 4 250.1900 20.20 14.69 46.00 25.80 100 180 Horizontal 5 545.0700 29.49 23.17 46.00 16.51 100 90 Horizontal 6 881.6600 35.68 29.77 46.00 10.32 100 180 Horizontal RESULT: PASS Report No.: AGC06023210201FE03 Page 51 of 83 EUT TWS Bluetooth earphone Model Name SA08 Temperature 25°C Relative Humidity 55.4% Pressure 960hPa Test Voltage Normal Voltage Test Mode Mode 7 Antenna Vertical NO. Freq. [MHz] Level [dBμV/m] Factor [dB] Limit [dBμV/m] Margin [dB] Height [cm] Angle [°] Polarity 1 40.6700 17.45 11.91 40.00 22.55 100 60 Vertical 2 58.1300 16.15 11.05 40.00 23.85 100 180 Vertical 3 107.6000 16.95 12.17 43.50 26.55 100 10 Vertical 4 139.6100 21.20 14.85 43.50 22.30 100 30 Vertical 5 449.0400 27.18 20.97 46.00 18.82 100 350 Vertical 6 768.170…

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Report No.: AGC06023210201FE03 Page 74 of 83 Right VIEW OF EUT(PORT) OPEN VIEW OF EUT Report No.: AGC06023210201FE03 Page 75 of 83 VIEW OF BATTERY INTERNAL VIEW OF EUT-1 Report No.: AGC06023210201FE03 Page 76 of 83 INTERNAL VIEW OF EUT-2 INTERNAL VIEW OF EUT-3 BT Antenna Report No.: AGC06023210201FE03 Page 77 of 83 INTERNAL VIEW OF EUT-4 Charging Dock TOP VIEW OF EUT Report No.: AGC06023210201FE03 Page 78 of 83 BOTTOM VIEW OF EUT FRONT VIEW OF EUT Report No.: AGC06023210201FE03 Page 79 of 83 BACK VIEW OF EUT LEFT VIEW OF EUT Report No.: AGC06023210201FE03 Page 80 of 83 RIGHT VIEW OF EUT VIEW OF EUT(port)-1 Report No.: AGC06023210201FE03 Page 81 of 83 VIEW OF EUT(port)-2 OPEN VIEW OF EUT Report No.: AGC06023210201FE03 Page 82 of 83 VIEW OF BATTERY INTERNAL VIEW OF EUT-1 Report No.: AGC06023210201FE03 Page 83 of 83 INTERNAL VIEW OF EUT-2 ----END OF REPORT---- Conditions of Issuance of Test Reports 1. All samples and goods are accepted by the Attestation of Global Compliance (Shenzhen) Co., Ltd (the “Company”) solely for testing and reporting in accordance with the following terms and conditions. The company provides its services on the basis that such terms and conditions constitute express agreement between the company and any person, firm or company requesting its services (the “Clients”). 2. Any report issued by Company as a result of this application for testing services (the “Report”) shall be issued in confidence to the Clients and the Report will be strictly treated as such by the Company. It may not be reproduced either in its entirety or in part and it may not be used for advertising or other unauthorized purposes without the written consent of the Company. The Clients to whom the Report is issued may, however, show or send it, or a certified copy thereof prepared by the Company to its customer, supplier or other persons directly concerned. The Company will not, without the consent of the Clients, enter into any discussion or correspondence with any third party concerning the contents of the Report, unless required by the relevant governmental authorities, laws or court orders. 3.The Company shall not be called or be liable to be called to give evidence or testimony on the Report in a court of law without its prior written consent, unless required by the relevant governmental authorities, laws or court orders. 4. The non-CMA report issued by AGC is only permitted to be used by the client as internal reference use and shall not be used for public demonstration purpose. 5. In the event of the improper use of the report as determined by the Company, the Company reserves the right to withdraw it, and to adopt any other additional remedies which may be appropriate. 6. Samples submitted for testing are accepted on the understanding that the Report issued cannot form the basis of, or be the instrument for, any legal action against the Company. 7. The Company will not be liable for or accept responsibility for any loss or damage however arising from the use of information contained in any of its Reports or in any communication whatsoever about its said tests or investigations. 8.Clients wishing to use the Report in court proceedings or arbitration shall inform the Company to that effect prior to submitting the sample for testing. 9. The Company is not responsible for recalling the electronic version of the original report when any revision is made to them. The Client assumes the responsibility to providing the revised version to any interested party who uses them. 10. Subject to the variable length of retention time for test data and report stored hereinto as otherwise specifically required by individual accreditation authorities, the Company will only keep the supporting test data and information of the test report for a period of six years. The data and information will be disposed of after the aforementioned retention period has elapsed. Under no circumstances shall we provide any data and information which has been disposed of after retention period. Under no circumstances shall we be liable for damage of any kind, including (but not limited to) compensatory damages, lost profits, lost data, or any form of special, incidental, indirect, consequential or punitive damages of any kind, whether based on breach of contract of warranty, tort (including negligence), product liability or otherwise, even if we are informed in advance of the possibility of such damages.

Test Setup Photos RADIATED EMISSION TEST SETUP BELOW 1GHZ RADIATED EMISSION TEST SETUP ABOVE 1GHZ CONDUCTED TEST SETUP