The Prescription Electronics COB is one of the most well known and vastly used vintage effects pedals to ever be designed. This unit appears to be all original and from the early to mid 1990's. It works exactly as it should and adds an upper octave pitch to your guitar lines. Between the Volume and Blend controls, this unit can also push your amp into a very sweet sounding overdrive or Fuzz-like gain tone. The Octave can then be  blended into its sweet spot. Comes with what appears to be the original hand written instructions.