Distance remote control, digital display showing radio wave frequency, volume level, track number. Frequency range: more than 200 radio waves, 87,5 MHz - 108 MHz, adjustment step 0.1 MHz, saving settings function (radio wave frequency, track number etc) 2.0 USB high-speed connecter. Powered via car cigarette lighter connecter (12V. D.C.) reads Mp3 files from USB flash disk (built-in memory) or SD card and transmits radio wave to the head unit via the wave with the same frequency. 4 basis functions: playback/pause/forward/back, radio wave adjustment, volume control.