Car Wireless Bluetooth Fm Transmitter Mp3 Player Usb Car Charger Adapter Features: Directly powered by a 12/24V car cigarette lighter, the car transmitter is fast and convenient for owners to play music via BT5.0 connection, or, plug in a memory disk(not included) with your favorite songs in it. Dual USB ports for Max. 3.1A output, you can charge two devices fast at the same time through it.  Built-in noise-cancelling microphone provides clear and high quality sound when making a phone call. Real-time monitor the car battery voltage, then display it digitally and clearly. Knob+Keys convenient operation to adjust the volume, switch songs, answer/hang up, and more.   Package Includes: 1 x Car Transmitter