This is a vintage Distortion ⅱ, which has become less common. It has a thick sound like a fuzz, but without the sound collapsing, and with clear high frequencies. I think it has a unique sound that can't be replaced. It has been active as the main distortion for both single-coil and humbucker pickups. Although it's labeled as a distortion, its range is quite wide, from crunch to overdrive to distortion at maximum gain. It's the type that draws power directly from the unit, and it has a wide range, so the guitar sound cuts through well even in an ensemble. The power plug has been replaced by the previous owner. Operation has been confirmed. As it is from the original specifications, the volume doesn't get very loud. Most users use it with the volume at full, but it can be used without any problems in that state.