The Car Stereo Output Converter allows the matching of aftermarket stereos of factory common ground systems and the addition of 2 or 4 channel amplifiers to most stereos without RCA outputs. It also allows the addition of amplifier and subwoofer to existing factory systems. The converter works with select Bose factory stereos and converts car stereo speaker outputs to RCA outputs. Suitable for car stereos with up to 80 watts per channel. With adjustable level matching from 0 to 2 volts