2AYB6-MU01052Rotary True Wireless Stereo Earbuds

SAILSKY ELECTRONIC LIMITED Address: Huixiang Road 5, Jinglian Community, Qiaotou Town, Dongguan, China Tel: +86-0769-81038177 E-mail:[email protected] Product Similarity Declaration Date: 2024-03-15 FEDERAL COMMUNICATIONS COMMISSIONS Autho rization and Evaluation Division 74 35 Oakland Mills Road Columbia, MD 21046 To Whom It May Concern, We,SAILSKY ELECTRONIC LIMITED hereby declare that we have a product named as Rotary True Wireless Stereo Earbuds (Model No.: MU0105 2; FCC ID:2AYB6-MU01052) was tested by Bay Area Compliance Laboratories Corp. (Shenzhen). meanwhile, for our marketing p urpose, the model MU01052 is available in three colors, they are identical in electrically, except for the difference of color. No other changes are made to them. We confirm that all information above is true, and we’ll be responsible for all the consequences. Please contact me if you have any question. Sincerely Yours, Signature: Printed Name: Tom Shen Title: Manager

SAILSKY ELECTRONIC LIMITED Address: Huixiang Road 5, Jinglian Community, Qiaotou Town, Dongguan, China Tel:+86-0769-81038177 E-mail:[email protected] Date: 2024-03-15 FEDERAL COMMUNICATIONS COMMISSIONS Authorization and Evaluation Division 7435 Oakland Mills Road Columbia, MD 21046 Declaration letter We, SAILSKY ELECTRONIC LIMITED hereby declare that we have a product named as Rotary True Wireless Stereo Earbuds (FCC ID:2AYB6-MU01052; Model No.:MU01052) was tested by B ay Area Compliance Laboratories Corp. (Shenzhen),which has left earbud and right earbud. we would like to declare that the product has two units which are electrically identical except for the following content. We confirm that all information above is true, and we’ll be responsible for all the consequences. Please contact me if you have any question. The red box in the picture below (Component tag number: R5), the left ear is NC. This does not affect RF parameters. Sincerely Yours, Signature: Printed Name: Tom Shen Title: Manager

SAILSKY ELECTRONIC LIMITED Address: Huixiang Road 5, Jinglian Community,Qiaotou Town, Dongguan,China Tel:+86-0769-81038177 E-mail:[email protected] Date: 2024-03-15 To: FEDERAL COMMUNICATIONS COMMISSION Authorization and Evaluation Division 74 35 Oakland Mills Road Columbia, MD 21046 We,SAILSKY ELECTRONIC LIMITED hereby declare that： Product Name: Rotary True Wireless Stereo Earbuds Model No.: MU01052 FCC ID: 2AYB6-MU01052 For BT Mode: EDR(8DPSK), BLE 1M/2M are disable by software. For Below are activated: Bluetoo th BDR(GFSK), EDR(π/4‐DQPSK) Except for the manufacturer, the end user does not have any capability to modify/change the RF parameters. We acknowledge that it is the manufacturer’s responsibility to provide the radio c onfigu ra tions to ensure compliance with Commission’s rules. Sincerely Yours, Signature: Printed Name: Tom Shen Title: Manager

CFR 47 §2.911(d)(5)(i) Attestation Letter SAILSKY ELECTRONIC LIMITED Address: Huixiang Road 5, Jinglian Community,Qiaotou Town,Dongguan ,China Tel:+86-0769-81038177 E-mail:[email protected] Attestation Letter Date: 2024-03-15 FEDERAL COMMUNICATIONS COMMISSIONS Authorization and Evalu ation Division 7435 O akland Mil ls Road Columbia, MD 21046 Ref: Attestation Stat ements CFR 47 §2.911(d)(5)(i) Filing FCC ID:2AYB6-MU01052 SAILSKY ELECTRONIC LIMITED(“the applicant”) certifi es t hat the equipment for which authorization is soughtis not “covered” equipment prohibit ed from receiving an equipment authorization pursuant to section 2.903 of the FCC rules. Sincerely, Signature Contact Person:T om Shen Title:Manager

CFR 47 §2.911 (d)(5)(ii ) Attestation Letter SAILSKY ELECTRONIC LIMITED Address: Huixiang Road 5, Jin glian Community,Qiaotou Town,Dongguan ,China Tel:+86-0769-81038177 E-mail:[email protected] Attestation Letter Date: 2024-03-15 FEDERAL COMMUNICATIONS COMMISSIONS Authorization and Evalu ation Division 7435 O akland Mil ls Road Columbia, MD 21046 Ref: Attestation Stat ements CFR 47 §2.911(d)(5)(ii) Filing FCC ID:2AYB6-MU01052 SAILSKY ELECTRONIC LIMITED (“the applicant”) certifies that as of the date of the filing of th e application, the a pplicant is not identif ied on the Covered Lis t as an enti ty producing “covered” equipment. Sincerely, Signature Contact Person: Tom Shen Title:Manager

SAILSKY ELECTRONIC LIMITED * the applicant must designate a contact located in the United States for purposes of acting as the applicant’s agent for service of process, regardless of whether the applicant is a domestic or foreign entity. An applicant located in the United States may designate itself as the agent for service of process. U.S. Agent Designation for Service of Process - Certification Attestation Letter 3/27/2024 TO: Federal Communications Commission 7435 Oakland Mills Road Columbia, MD 21046 ATTN.: Reviewing Engineer FCC ID: 2AYB6-MU01052 FRN of applicant: 0030231625 Per section 2.911(d)(7) of the FCC rules, SAILSKY ELECTRONIC LIMITED (“the applicant”) certifies that the equipment for which authorization is sought is designated to the following U.S. agent* for service of process: Company Name: Stariver Consulting Company FCC Registration Number (FRN): 0033610684 Physical U.S. Company Address: 2363 James St #1098 Syracuse, NY 13206, USA Contact Person: Chong He Agent Email Address: [email protected] The above contact person accepts the obligation for service of process. The applicant accepts to maintain an agent for no less than one year after the grantee has terminated all marketing and importation or the conclusion of any Commission-related proceeding involving the equipment. Applicant Signed: Agent Signed: Signed: Printed name: Tom Shen Title: Manager Company Name: SAILSKY ELECTRONIC LIMITED Date: 3/27/2024 Signed: Printed name: Chong He Title: Manager Company Name: Stariver Consulting Company Date: 3/27/2024

SAILSKY ELECTRONIC LIMITED Address: Huixiang Road 5, Jin glian Community,Qiaotou Town, Dongguan,China Tel:+86-0769-81038177 E-mail:[email protected] FCC Authorization Date: 2024-03-15 FEDERAL COMMUNICATIONS COMMISSIONS Authorization and Evaluation Division 7435 Oakland Mills Road Colu mbia, MD 21046 Subject: Agent Authorization To whom it may concern: We, SAILSKY ELECTRONIC LIMITED th e undersigned, hereby authorize Bay Area Complia nce Laboratories Corp. (Shenzhen) to act on its behalf in all matte rs relating to ap plication for Equipmen t a uthorization, including the signing of all documents relating to th ese matters. All acts carried out by Bay Area Compliance Laboratori es Corp. (Shenzhen) on our behalf shall have the same effect as our own action. We, the undersigned, hereby certify that we are not subject to a denial of federal benefit s, that includes FCC be nefits, pursuant to Section 5301 of the Anti-Drug Abuse Act of 1988, 21 U.S.C. 862. This authorizat ion is valid until further written notice from the applicant. Sincerely Yours, Signature: Printe d Name: Tom Shen Titl e: Manager

SAILSKY ELECTRONIC LIMITED Address: Huixiang Road 5, Jinglian Community, Qiaotou Town, Dongguan, China Tel:+86-0769-81038177 E-mail:[email protected] FCC ID Cover Letter Date: 2024-03-15 We, SAILSKY ELECTRONIC LIMITED, hereby submit justification for placing the FCC certification No. in the associated user’s manual and charging case. According to the FCC regulation, the FCC certification No. should be printed on the earbuds, but as the earbuds are too small to print the label (FCC ID: 2AYB6-MU01052), it will be moved to the user manual and charging case. The details are as below: A. Side surface (A): The side surface does not provide enough physical space to fit the printing of the FCC certification No. according to below reference picture. B. Top cover (B): The top cover does not provide enough physical space to fit the printing of the FCC certification No. according to below reference picture. Conclusion: Based on the above description of area A to B, we conclude that the device is unquestionably too small for enabling the FCC certification No. to be printed onto any surface. We therefore request to move the FCC certification No. to the user’s manual and charging case. Label and label location: Sincerely Yours, Signature: Printed Name: Tom Shen Title: Manager

Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 1 of 7 EXHIBIT B - EUT EXTERNAL PHOTOGRAPHS Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 2 of 7 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 3 of 7 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 4 of 7 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 5 of 7 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 6 of 7 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 7 of 7

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 in- terference that may cause undesired operation. Model No.: MU01052 Input: 5V 200mA Battery Capacity: 250mAh FCC ID: 2AYB6-MU01052 Made in ChinaEarphone battery capacity: 35mAh Size: 39.5 x 22mm Label Label location

Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 1 of 8 EXHIBIT C - EUT INTERNAL PHOTOGRAPHS Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 2 of 8 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 3 of 8 Antenna Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 4 of 8 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 5 of 8 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 6 of 8 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 7 of 8 Bay Area Compliance Laboratories Corp. (Shenzhen) Project No.: SZ3240311-12072E-RF Page 8 of 8

Circuit Description The equipment under test is a 2.4GHz transceiver with 79 channels operating at 2402 - 2480 MHz. It is powered by 3.7VDC (1 Li-battery). It connects to the Wii console by Bluetooth protocol. Channel List: Frequency(MHz): 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 Modulation Type: GFSK, π/4-DQPSK Antenna Type: SMD CERAMIC ANTENNA Antenna Gain：2.78dBi The functions of main Components are mentioned as below. 1) U7(AC7023D2) acts as Bluetooth ic. 2) U6(XB4302A) acts as Li- battery protection ic 3) X1 acts as crystal 24MHz

Bay Area Compliance Laboratories Corp. (Shenzhen) Report No.: SZ3240311-12072E-RF-00 TR-EM-RF001 Page 11 of 64 Version 1.0 (2023/10/07) FCC§15.247 (i), §1.1307 (b) (1) & §2.1093 - RF EXPOSURE Applicable Standard According to FCC §2.1093 and §1.1307(b) (1), systems operating under the provisions of this section shall be operated in a manner that ensure that the public is not exposed to radio frequency energy level in excess of the Commission’s guideline. According to KDB 447498 D01 General RF Exposure Guidance 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 1. f(GHz) is the RF channel transmit frequency in GHz. 2. Power and distance are rounded to the nearest mW and mm before calculation. 3. The result is rounded to one decimal place for comparison. 4. When the minimum test separation distance is < 5 mm, a distance of 5 mm is applied to determine SAR test Exclusion. Measurement Result For worst case: Mode Frequency (MHz) Max tune-up conducted power # (dBm) Max tune-up conducted power # (mW) Distance (mm) Calculated value Threshold (1-g SAR) SAR Test Exclusion Bluetooth 2402-2480 3.00 2.00 5 0.63 3 Yes Result: Compliant

5 5 4 4 3 3 2 2 1 1 DD CC BB AA DAC_L DAC_R USBDP USBDM LED_BR BAT BTXOSCO BTXOSCI B T _ AVDD A G ND DC 5V VDDIO VCOM LED_BR GND SWBT-RF USBDM USBDP M IC DACLDACR PP/ ON PP/ON DAC_LDAC_RDACLDACR MIC MIC_BIAS M IC _ BIAS USBDM LR_DET L R _ DET BAT- BAT- BAT- BTXOSCIBTXOSCO DC5V BT_AVDD BAT B- C29 1.2pF C4 104/10V C10 NC DP C18 15pF R79NC 5V C28 1.2pF NTC1 NC C16 NC U7AC7023D2 VCOM 1 VDDIO 2 SW 5 VBAT 6 L D O_ IN 7 B T _ AV DD 8 OSCI 12 PB6/ADC9 3 PB 2 / L P _ T H1 9 PB 1 / L P _ T H0 10 BT_RF 11 ADC5/PC5/USBDM 14 OSCO 13 ADC4/PC4/USBDP 15 AI N _ A 0 /PA1 16 D A C VSS 20 D A CL 19 D A CR 18 AI N _ A 1 /PA2 17 G ND 0 PGND 4 B+ C19 15pF U6 XB4302A GND 1 GND 3 VDD 4 VM 2 C11 105/10V L433nH C12 106/16V R3100R R+ C13104/10V L1100R D2 W 1 2 R- K1 X124MHz-12pF-10ppm 1 2 3 4 L333nH IN OUT GND GND MIC3 GTM2718AT421 3 1 4 2 C23 105/10V R5 1K DM L52.2nH ANT2 HZ1608WA01 1 1 2 2 GND C9 105/16V C20 105/16V L210uH Left R5: NC Right R5: 1K

SMD CERAMIC ANTENNA Data Sheet For 2400-2500MHz 1.6x0.8x0.4mm [EIA1608] H CS-2450-16-A Z1608WA01 Manufacturer: Shenzhen Haizhe Technology Co., Ltd. Address: C3, Building A1, Red Box Creative Park, No. 11 Huancheng South Road, Ma'antang Community, Bantian Street, Longgang District, Shenzhen Chip Antenna Feature nLight weight, compact nWide bandwidth, low cost nBuilt-in antenna with high gain nOperating Temp. : -40°C~+85°C Application nBluetooth nWLAN 2.4 nWiFi 5/6/6E nUWB CS-2450-16-A Electrical Characteristics per line(TA=25°C) Parameter Specification Units Frequency Band 2400~2500 MHz Polarization Linear *Peak Gain 2.78 dBi *Peak Efficiency 80.25 % Impendance 50 Ω Test condition: Test board size 70*60 mm; Matching circuit: Pi matching circuit will be required. Product Dimension Units:mm W A L A H LWHA 1.60±0.200.80±0.200.40±0.100.2±0.07 Recommend PCB Layout1 Chip Antenna Test condition: Test board size 70*60 mm; Top Layer (unit mm) Bottom Layer (unit mm) Feeding line:50Ω Chip Antenna E1(0201) 1.5 3.5 1.0 0.5 0.5 0.5 2.0 E2(0201) 1.5 3.5 2.0 E3(0201) 0.5 ANT 1.1 Note:The spacing between antenna pads should not be ＜ 1.1mm 注意:天线焊盘内间距不能＜1.1mm 6.5 6.5 1.1 0.5 0.8 Recommend PCB Layout2 Chip Antenna Test condition: Test board size 70*60 mm; Top Layer (unit mm) Bottom Layer (unit mm) Chip Antenna Feeding line:50Ω E1(0201) 1.5 2.0 0.5 0.5 0.5 10 ANT 2.5 1.5 10 E2(0201) E3(0201) 0.5 1 . 1 Note:The spacing between antenna pads should not be ＜ 1.1mm 注意:天线焊盘内间距不能＜ 1.1mm 1.1 0.5 0.8 Typical Characteristics Fig. 1 Return Loss Radiation Pattern The Gain pattern is measured in FAR -field chamber. DUT is placed on the table of rotator , a standard horn antenna and Vector Network Analyzer is used to collect data. Fig.2 FAR-field Chamber Chip Antenna Chip Antenna Equivalent circuit: Chip Antenna RF chip ANT E1 E2 E3 Frequency 2400MHz2450MHz2500MHz Avg. gain - 1.92- 1.35- 1.56 Peak gain 1.792.782.66 Efficiency 74.5580.2576.98 Radiation Performance: 2D Gain Pattern X-Y Plane Y-Z Plane X-Z Plane Item Condition Specification Thermal shock 1. 30±3 minutes at -40 ° C±5 ° C , 2. Convert to +105 ° C (5 minutes) 3. 30±3 minutes at +105 ° C±5 ° C , 4. Convert to -40 ° C (5 minutes) 5 . Total 100 continuous cycles No apparent damage Fulfill the electrical spec. after test. Humidity resistance 1. Humidity: 85% R.H. 2 . Temperature: 85±5 ° C 3 . Time: 1000 hours . No apparent damage Fulfill the electrical spec. after test. High temperature resistance No apparent damage Fulfill the electrical spec. after test. 1 . Temperature: 150 ° C±5 ° C 2 . Time: 1000 hours . Low temperature resistance 1 . Temperature: -40 ° C±5 ° C 2 . Time: 1000 hours . No apparent damage Fulfill the electrical spec. after test. Soldering heat resistance 1. Solder bath temperature : 260±5°C 2. Bathing time: 10±1 seconds No apparent damage Solderability The dipped surface of the terminal shall be at least 95% covered with solder after dipped in solder bath of 245±5°C for 3±1 seconds . No apparent damage (a)At warehouse: The temperature should be within 0 ~ 30°C and humidity should be less than 60% RH.The product should be used within 1 year from the time of elivery (2)Storage Condition . (b)On board: The temperature should be within -40 ~85°C and humidity should be less than 85% RH. Operating temperature range : -40°C to +85°C ( 3 ) Operating Temperature Range . Recommended Reflow Solder curve Chip Antenna External Dimensions L*W (mm) 1.6*0.8 Central Frequency 2450 MHz Product Series: Chip Antenna Marking ABCDEFLW 8.00±0.33.50± 0.051.75±0.12.00±0.054.00±0.11.50±0.12.30± 0.11.55± 0.1 Part Number System CS - 2450 - 16-A Package Information Chip Antenna Note the follows, in case of using solder gun for replacement (1)Soldering Gun Procedure . (a) The tip temperature must be less than 350°C for the period within 3 seconds by using soldering gun under 30 W. (b) The soldering gun tip s hall not touch this product directly. (2) Soldering Volume Note that excess of soldering volume will easily get crack the body of this product. The contents of this data sheet are subject to change without notice. Please confirm the specifications and delivery conditions when placing your order. 订货信息Order Information Chip Antenna Date Revision Description of changes 2023-01-03 1.0 First Version 2023-11-151.1 Add PCB Layout Device Package Net Weight Carrier Quantity HSF Status CS-2450-16-A 1608 0.002g Tape&Reel 5000pcs RoHS compliant Revision history