Product Specifications: Built-in Bluetooth + microphone. Hands-free calls Supports Advanced Audio Distribution Profile Off time display function Digital high-quality FM stereo radio, Preset 18 stations (frequency: 87.5-108 MHz) Support USB / SD / MMC card reader Support Audio: MP3 / WMA / WAV, etc. Support folder function Support breakpoints and ID3 Play Support Remote control Rotary Volume Control MP3 randomized, 10 track up / down playback Electronic control volume treble, bass, balance and fader Multiple EQ Scene Selection: jazz, rock, pop, classical, etc. Mute and Loudess control L / R RCA audio output jacks 4-channel high power output (4 loud speaker) Machine size: 178 mm (W) * 50MM (H) * 125 mm (D) Overall dimensions: 188 mm * 58mm (H) Test voltage:12vpacking list 1 x Bluetooth car stereo player1 x remote control2 x power cables1 x user manual2 x key.Safety warning: 1. It is for 12v power only. It will burn out if installed in 24v power.2.This product installation needs professional skills. If not, please go for professional help. Details refer to the instruction manual.