This seems to be a quality built item. Although the description on here is vague the unit is actually better than the description. It Controls MP3 players through the usb charging chord, it has auxiliary in hookups, and the option to turn the rear RCA line out to subwoofer only. Its is easy to use and feels solid. My only complaint is the power output for the speakers isn’t exactly stellar. But with the plethora of cheap marine amps on the market that is easily solved.