FM Transmitter device from Compass 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 or AUX cable (not included) and from external MicroSD memory cards. Additionally, through port USB, you can easily charge your smartphone. Finally, it is powered by the car's cigarette lighter.