For universal radio transmission from signal sources with a 3.5cm jack connection like an MP3 player smartphone tablet PC to any car radio Signals are transmitted via radio to the selected FM frequency of the car radio Auto scan function the device searches the best possible free FM frequency 3 station memories for preset frequencies Type of modulation FMPower supply via integrated cigarette lighter plug Additional USB (Universal Serial Bus) socket with 1A for charging MP3 players & smartphones