FM Transmitter FunctionOur FM Bluetooth transmitter car adopts Bluetooth 4.2 technology, compatible with iPhone, iPad, iPod, tablet and Android smartphones. 3 Playback ModesA: Play music from Bluetooth-enabled devices via FM signal; B: Transfer music from U disk (up to 64GB); C: Stream music from your MP3 player, tablet, etc. via 3.5mm audio cable Transmit to car stereo. Dual USB PortsThis USB car charger car kit with dual USB ports. The 5V/3.1A USB charging port can fully charge your devices such as smartphones and iPads in a short time, and the other with a USB icon is a USB file designed for reading. Easy to UseCar battery voltage display and automatic connection. When the bluetooth transmitter car auxiliary is plugged into the car cigarette lighter, the car voltage is displayed. The memory function makes it possible to automatically connect to the last paired phone. High Stereo SoundEffortless and clear hands-free calling with CVC noise reduction technology. Easily answer/hang up/reject calls/recall the last number/adjust the volume through multi-function buttons, while listening to your mobile phone music and audio GPS navigation, the latest noise reduction technology ensures call quality and playback sound quality comparable to CD playback .