This is a vintage Schaller Double Pedal or "Doppelter Fußpedal" made in the late 60's / early 70's. This extremely rare pedal is one of the first Multi-FX pedals. It features a killer Germanium fuzz (thanks to several AC151V's), a treble boost, and Schaller's perhaps best known effect: tremolo. Two foot pedals allow you to control your overall volume (schwell) and intensity of your selected effect (effekt). The toggle switch between the pedals toward the bottom is your pedal bypass switch, the switch near the top engages your fuzz, the switch on the side toggles between treble-boost, tremolo, and off, and the wheel on the opposite side controls the speed of your tremolo. There's a lot going on here, but it's all worth the learning curve! Be sure to listen to our demo below - we go through each effect throughout the clip!It looks to be all original but the battery door. Built like a panzer tank, the Doppel pedal is in fantastic cosmetic and functional condition!Please feel free to ask any questions, or call us for an in-hand description.Division Street Guitars914-737-2630