The pedal has a compressed, deep effect to allow equal sustain throughout the fretboard. Tone control was specifically designed to allow tones from the mellow fuzz, through slight mid cut to thin bright fuzz.
The FRF is not another variation of a classic fuzz design but a unique pedal with its own character and extremely versatile Tone control. It is great for recording different layers of Fuzz tones from haunting dark to cutting thin bright. Whatever setting you use the tone is always very musical and controllable.
The factory version has a little lower gain on minimum setting so it is easier to use in front of overdrive amp or pedals.