The Tone Corset, our new four-knob analog compressor, squeezes your guitar tone in all the right ways! Mike Matthews says, "The Tone Corset is the funkiest analog compressor I ever heard on guitar!"-Four-knob design provides excellent control and gives the user the ability to precisely shape their instrument’s dynamics. -The Sustain knob controls the amount of compression applied to the guitar signal. -The Attack know adjusts how quickly the compressor recovers. As Attack is turned clockwise the pedal’s response is slower and more initial pick attack comes thru. -The Blend knob adjusts the mix of the dry and compressed signals. -Volume controls the overall output level. -The Pad switch pads down the input signal to prevent undesirable distortion if the Tone Coret is used with high output humbuckers, bass guitar, etc. -True Bypass for maximum signal path integrity. -Comes with a 9Volt battery.