RCA Audio Noise Filter Suppressor Ground Loop Isolator for Car and Home Stereo 100% Brand New, High Quality Eliminate ground loop humming and buzzing noise between an audio source and an amplifier. When used with car audio, this isolation circuit goes between the head unit and the amp or EQ. Passive in-line device Current Rating: 20A Rated input: 30W Peak Input: 60W Dimensions: 35X65MM