1. FCC ID
  2. B4O
  3. B4O-HSJM320

FCC ID B4O-HSJM320

Wireless Over-ear Headphones

by GT-tronics HK Ltd

Grantee Code: B4O   Product Code: HSJM320
Latest application date: 2026-10-22

FCC ID Device Details

FCC IDB4O-HSJM320
Mirrorsfcc.id | gov | fccid.ai
Grantee CodeB4O
Product CodeHSJM320
Applicant BusinessGT-tronics HK Ltd
Related Domains gt-tronics.com picus.fi
Equipment ClassWireless Over-ear Headphones
Test FirmShenzhen BALUN Technology Co., Ltd.

Operating Frequencies

Frequency RangeApplication PurposeFinal Action Date
2402-2480 MHzOriginal Equipment2026-10-22

Exhibits

DocumentTypeAvailableFile
ID Label/Location InfoID Label/Location Info2026-10-22PDF 201.2 KB
Antenna SpecificationTest Report2026-10-22PDF 554.7 KB
Test ReportTest Report2026-10-22PDF 3.2 MB
Covered Equipment Certification Attestation LetterAttestation Statements2026-10-22PDF 29 KB
FCC U.S. Agent Designation AttestationAttestation Statements2026-10-22PDF 55.9 KB
Authority to Act as AgentCover Letter(s)2026-10-22PDF 33.4 KB
Request for ConfidentialtyCover Letter(s)2026-10-22PDF 135.3 KB
RF Exposure InfoRF Exposure Info2026-10-22PDF 1.3 MB
RF Exposure Info-ACRF Exposure Info2026-10-22PDF 4.6 MB
RF Exposure Info-APRF Exposure Info2026-10-22PDF 212.7 KB
RF Exposure Info-ASCRF Exposure Info2026-10-22PDF 137 KB
RF Exposure Info-ATDRF Exposure Info2026-10-22PDF 179.6 KB
Users Manual Metadata onlyUsers Manual2027-04-21PDF 1 MB
Internal Photos Metadata onlyInternal Photos2027-04-21PDF 743.4 KB
External Photos Metadata onlyExternal Photos2027-04-21PDF 619.9 KB
Test Setup Photos Metadata onlyTest Setup Photos2027-04-21PDF 741.2 KB
Test Setup Photos-SAR Metadata onlyTest Setup Photos2027-04-21PDF 68.1 KB
Block Diagram Metadata onlyBlock DiagramPDF 167.4 KB
Schematics Metadata onlySchematicsPDF 65 KB
Operational Description Metadata onlyOperational DescriptionPDF 442.6 KB
Tune Up Metadata onlyParts List/Tune Up InfoPDF 44.6 KB

Application Information

Application IDVM4OYR6CUss/28n+BS4XOw==
Final Action Date2026-10-22
Application PurposeOriginal Equipment
Applicant FRN0021630322
ModelHSJM320
Frequency Range2402-2480 MHz
Equipment ClassDTS - Digital Transmission System
Device DescriptionWireless Over-ear Headphones
Responsible PartyDennis Wong, dwong@gt-tronics.com , +852-8100-1820
Non-Technical ContactIvan Wang, Picus Advisors US LLC, ivan.wang@picus.fi , (713) 391-4488
Test FirmHanson Lin, Shenzhen BALUN Technology Co., Ltd., Hanson.Lin@baluntek.com , 86-755-66833830
TCB EmailTCB@nemko.com
TCB ScopeA4: UNII devices & low power transmitters using spread spectrum techniques
Short-Term ConfidentialityYes
Long-Term ConfidentialityYes
Modular EquipmentDoes not apply
Composite DeviceYes
Cognitive RadioNo
Authorization WaiverNo
Authorization Waiver ApprovedNo
Section 5301 CertificationYes
Related OET Knowledge DataBase InquiryNo

Applications

Application IDDatePurpose
VM4OYR6CUss/28n+BS4XOw==2026-10-22Original Equipment

Equipment Authorization

FrequencyOutputRules
2402-2480 MHz0.0101115C

Grants

TCB Grant - Application VM4OYR6CUss/28n+BS4XOw==

TCB GRANT OF EQUIPMENT
AUTHORIZATION		 TCB
Certification
Issued Under the Authority of the
Federal Communications Commission
By:

  Nemko North America, Inc.
303 River Road
Ottawa, Ontario, K1V 1H2
Canada 		Date of Grant: 10/22/2026

Application Dated: 10/22/2026
GT-tronics HK Ltd
Unit 10, 2/F., Block B, Tonic Industrial
Center 19 Lam Hing Street, Kowloon Bay,
Kowloon,
Hong Kong
 
Attention: Dennis Wong , Admin Asst

NOT TRANSFERABLE
EQUIPMENT AUTHORIZATION is hereby issued to the named GRANTEE, and is VALID ONLY for the equipment identified hereon for use under the Commission's Rules and Regulations listed below.
 
FCC IDENTIFIER:  B4O-HSJM320
Name of Grantee:  GT-tronics HK Ltd
Equipment Class: Digital Transmission System
Notes: Wireless Over-ear Headphones
Grant Notes  FCC Rule Parts Frequency
Range (MHZ) 		Output
Watts 		Frequency
Tolerance 		Emission
Designator
15C 2402.0  -  2480.0 0.01011  

Output power listed is conducted. The highest reported SAR for Head is 0.13 W/kg.