The CastleRock Guitar Compressor Pedal provides very smooth sustain and helps to give a more balanced string response. Alone this pedal provides a punchy clean sound with sustain trails but when paired with a distortion or chorus your tone will have a beefed up harmonic tone. The CastleRock Compressor may just be a pedal you leave on at all times! Quiet operation and switching. All metal chassis, rubber footswitch tread , non slip rubber back.