IMAGE REFERENCEL. The FM modulator is mainly used in automoviles as an economic replacement for a digital player ( MP3 player, CD player). The FM transmitter allows you to make calls in loud mode and listen to music. The phone synchronization with the FM transmitter is performed via Bluetooth V5.0. Additional channel: 87.5 ~ 108 MHz. Connect the device to the car cigarette lighter, switch it to the FM radio mode and make sure the FM transmitter frequency matches the vehicle transmitter. With the button (CH), you can adjust the transmitter's FM band by pressing it and adjusting it in time or timeline. The modulator with 2 USB ports (3.1a/1A) allows you to quickly load mobile devices. Call management: A call button push is enough to answer or end an incoming call. Double-click the call button to call the last number.