In production for over a decade starting in the mid-1960s, the  bounced through several iterations during its run. Those examples were built by Sola Sound’s Gary Hurst chiefly using the  circuit. The earliest Supa Fuzz’s actually used a version of the MkI circuit and boasted a tone filter and pre-set gain levels. The Supa Fuzz was popularized by the likes of Pete Townshend, Jeff Beck and the late Ron Asheton. Today, some of the more popular versions of the Supa Fuzz will set you back a few thousand dollars. There are a few builders that make clones of the pedal.