Stinger SGN21 Pop Stopper Protect your system from harmful turn on / off noise Delays the amplifier(s) turn-on lead 1 second to eliminate undesirable pops from the amplifier(s) when turning on an audio system or eliminates ignition turn off pops by allowing the amplifier to turn off 1 second before the radio 55-watt high power inputs per channel Works on Amplifiers, Speakers or Source Units 55-watt high power inputs per channel Converts speaker wires to RCA DC isolation for noise reduction Adjustable low level output for amplifiers