Griffin Itrip Auto Universal Plus Refresh FM transmitter and PowerJolt Auto Charging for Portable Audio Players Send your music wirelessly to your FM radio so you can listen through your own speakers Works with almost any portable audio device with a standard 1/8-inch headphone jack Powered by your vehicles 12 volt accessory outlet or cigarette lighter Transmits 88.1  107.9 MHz FM frequencies so you can find a spot with the least interference Built-in USB port for charging your device