Features: Two Channel ground Loops isolator Small Size Designs, fits in small places and produces great result Reduces High Pitched Whine Alternator Noise caused by the car's electrical Systems Eliminate ground Loops humming and buzzing noise between Radio source and amplifier. When used with car Radio, this isolation circuit goes between the head unit and theamplifier. Power supply noise of igniters produces filtration effect, make the sound effect is better. Specifications: Material:ABS Current Rating: 20A Rating input: 30W Pk Input: 60W Size:Approx.65mm/2.56''x35mm/1.38'' Package Includes: 1Piece Noise Filter note: Please allow 1mm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual color of the item.