Car Bluetooth FM transmitter: the phone, U disk, MP3 music inside to the car audio player Car Charging: You can charge smart phone through USB interface. Bluetooth hands-free car: cell phone Bluetooth hands-free calls through a key. Car USB: USB disk can read through the USB interface high-fidelity stereo, using DIGITAL, PLL phase-locked loop technology LCD display frequency, choose more convenient; all-point launch (up to 200 frequencies can choose) with power-off memory, can store the current frequency of play direct keys, play / pause, the previous song / next song Product Features: FM transmitterFrequency voltage display Independent Bluetooth start / shutdown button Line audio input Support U disk to play music Support MP3 / WMA music format Can answer / hang up / reject / re-send via Bluetooth Bluetooth stereo music player Call echo cancellation and noise reduction (CVC) technology Dual USB charging output, to other devices can provide voltage up to 5V / 2.5APower frequency automatic memory function Car battery voltage display Comes with a cigarette hole, more choices High-definition LCD display, more options 180 ° rotation for the screen