It is able to change the audio signal into frequency modulation signal and transmit wirelessly to the sound box of the car and play. No need to change any original equipment and is convenient and economic. Fashionable, smart, stereo voice and convenient operation, frequency is FM107.7±5MHz and is changeable. Multi-function make you have your own FM channel; unnecessary to change the MP3, CD of your car. The products adopt the latest 3D technology and make the tone same as laser and CD and television. It has been adopted phase lock loop technology, which ensures stable frequency radiation while functioning at a distance of up to 30M without dead areas so that you can still enjoy HI-FI music at home of in our car. It is built-in with U disk.