For universal radio transmission of signal sources with a 3.5 mm jack connection, such as MP3 players, smartphones, and tablets, to any car radio. Signals are transmitted via radio to the tuned FM frequency of the car radio. The auto scan function allows the device to search for the best possible free FM frequency at the touch of a button. It includes three preset frequency options. Modulation type: FM. Power supply is provided via an integrated cigarette lighter plug, and there is an additional USB socket with 1A power for charging MP3 players and smartphones.