In Transmitter mode, turn a non-Bluetooth TV, PC, CD player, for , MP3 / MP4 into Bluetooth transmitter. Receiver mode: perfect for home or vehicle music streaming sound system.Connect this bluetooth audio receiver to your line-in or aux input on your speakers, pair it to your bluetooth device, and enjoy the wireless music revolution. Whether you want Bluetooth convenience in your car, through your home theater system, in your kitchen, bathroom, or bedroom, etc. audio codec for a richer and sound experience. Listening to CD-like audio quality at no compromise. Easy operation, 3.5mm Male to Male Audio Connector or 3.5mm Male to Male Audio Cable to connect the speakers and receiver.Powerful bluetooth IC, More stronger compatibility. Powered by built-in rechargeable li-ion battery via mini USB port, long working hours and low consumption. ( included) You can through your car and answer phone call through the built-in Microphone. Specifications: Bluetooth version: V5.0+ Bluetooth protocol: AD2P Working distance: 10 meters Function: Bluetooth audio receiver / Bluetooth audio transmitter Colour:Black Material:PC + Metal Size:4.2*2.5*1.1cm Package Contents: 1 * USB Bluetooth Audio Adapter 1 * AUX cable 1 * Instruction manual Notes: 1. Power on / off Power on: hold the ON / OFF button for 5-7 seconds see a "ready to connect or a sound", it will auto connect the phone that was paired. Power off: press and hold the ON / OFF button for 4-5 seconds see a "Get long or red LED". 2. Connect the receiver to your speakers With 3.5mm Male to Male Audio Connector or 3.5mm Male to Male Audio Cable to the speakers and receiver (if no sound, make sure it was inserted completely). Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.