This pedal was originally designed for J.Mascis of Dinosaur Jr. He requested two Box of Rock pedals in one box with two stomp switches. He uses that regularly on stage now, but ZVex did one (or two) better with this version. You can adjust the sub frequencies (like the Distortron), and you can convert either channel to a Super Hard-On. In this way, you can configure the pedal to be two Distortrons cascaded, two Super Hard-Ons cascaded (like a Super Duper 2-in-1), or a Box of Rock with boost, or a Super Hard-On (SHO) going into a Box of RockTM. Distortion/boost heaven! Whee!!!