FM Transmitter device T831 for easy and quick music playback on any car stereo with a radio, without any additional actions. Choose an empty frequency that no active radio station broadcasts and synchronize the FM Transmitter device and your stereo to the same frequency, to listen to music from your car speakers. It features a Handsfree function so you can receive calls and have open conversation. It supports music playback directly from your mobile phone via Bluetooth, while also having port USB for charging your smartphone. Finally, it is powered by the car's cigarette lighter.