iRV35 car stereo is featured independent Zone 3 control and supports Bluetooth/HDMI/ARC/AM/FM/CD/DVD/MP3/MP4/Clock, providing digital 2.1 Surround Sound-optical SPDIF Audio Input. This RV stereo has digital amplifier for audio output, no heat low temperture in your mounting cabinet. USB is used to play music, video and photo file, also used to charge Android phones.