The Bluetooth Hands-Free Fm Transmitter provides a live full duplex communication solution. It uses Bluetooth technology through FM transmission to your FM car radio. This unit allows you to speak to callers through a built-in DSP microphone (it turns your car stereo into a Giant Bluetooth Headset). Simple to use, without the use of external wires, or expensive custom installation. The device is pair-able with any phone equipped with Bluetooth hands-free and stereo A2DP function. Bluetooth A2DP technology enables wireless transmission of music from your iPhone (OS 3.0 Software Update required). With the Bluetooth Hands-free Fm Transmitter, you are ready to listen to your favorite tunes without any wire connection!