Music Streaming Adapter and Player: Wireless Bluetooth FM Transmitter Adapter supports Bluetooth/USB disk/TF card/MP3/WMA player. Anti-interference performance and CVC technology. Automatically connects to memory pairing at power on.MORE COMPATIBILITY: This Bluetooth cigarette lighter adapter can transmit calls/MP3 music/cell phone sound to car radio.HANDS-FREE FUNCTION: The car Bluetooth adapter has a built-in microphone and call handling function, which automatically switches from music playback to hands-free mode when answering a call.CAR BATTERY VOLTAGE AND PORTABILITY: The car auxiliary Bluetooth adapter displays the voltage for 3 seconds when plugged into the outlet port. Always keep the battery healthy. It then switches to auto play mode. The Bluetooth transmitter has a compact and portable design.PC interface type: USB.Material: Flame retardant ABS