This product is a special Bluetooth car charger that can switch the call to a hands-free state via the professional Bluetooth module as long as the mobile phone is provided with the Bluetooth function. When the call is finished, it will be switched to the music play automatically. It can also send the music in your phone to your car sound wirelessly. You can enjoy the music and answer the call in hand-free mode without refitting your car, which ensures driving safety while enjoying music. BLUETOOTH FM TRANSMITTER : Transmit music from Bluetooth devices such as smartphones/tablets to car FM stereo systems by Bluetooth which is much cheaper than buying a Bluetooth car radio. COMPACT & PORTABLE: Unlike those bulky transmitters, the Aquarius FM transmitter is smaller and more space-saving, fitting your car cigarette lighter easily for safe driving. HANDS-FREE CALLING: Hands-free Calling With this wireless device, you can conveniently answer/ reject/redial calls through a hands-free function. Noise and wind will be suppressed by CVC technology, creating full duplex sound quality. Features: Bluetooth hands-free FM Transmitter Transmit music from your mobile to car stereo via Bluetooth Can be used as a hands-free car kit during driving via Bluetooth Enjoy calls and music while driving Supports charge by USB port Box Contains: 1x SoundZ FM Transmitter