The Ultimate Octave is a take on the Super Fuzz and Boss FZ-2. The Octave up is on a foot switch, and the Fat mode scoops them pesky mids.
The pedal is a near 1 for 1 clone of the Fulltone Ultimate Octave. The octave diodes between the two match, and the only difference is it's louder which is due to reducing a resistor on the output transistor.