Specifications: Product Name: 4 in 1 USB Bluetooth adapter Core functions: Bluetooth receiver or Bluetooth transmitter or PC transmitter or computer external sound card Bluetooth version: V5.1 Port type: USB, 3.5mm AUX Bluetooth Protocol: A2DP, AVRCP, HSP, HFP Transmission rate: 10 (Mbps) Operating frequency: 2400 (MHz) Color: Black Material: Fireproof ABS Transmission distance: Barrier-free 15-20 m Using Method: Drive free Size£º 41x19x10mm Support Devices: All kinds of speakers¡¢desktop computer¡¢ laptop¡¢ TV¡¢ power amplifier¡¢projector Features: 1. Transmitter Mode (TX): Wirelessly transfer audio from your non-TV, home stereo system, or CD player to your headphones or speakers. 2. PC Audio Transmitter Mode: Wirelessly transfer audio from the PC, notebook to headset, or speaker through a USB port, no audio cable is required. 3. Receiver Mode (RX): Wirelessly transfer audio from your -enabled phone, tablet, or computer to your wired stereo, speakers, or headphones. 4. Sound card mode (SC): USB external sound card, solve the problem of damage to the sound card of the computer, expand the AUX audio interface, and easily connect wired headphones or speakers or headsets. 5. Mini size: With an anti-scratch matte process, the body is small and portable. Package Includes: 1x Bluetooth5.0 transmitter-receiver 1x 3.5MM Audio cable 1x instructions