From Electro Harmonix;

The new Flatiron Fuzz is a classic op-amp powered fuzz/distortion. With
its late 70s style circuit and symmetrical hard clipping, its EHXs
take on the RAT2 pedal, only we think its better.

The Flatiron Fuzz is extremely versatile. At lower drive settings it
remains fairly clean and adds a pleasing mild distortion. As the drive
is turned up it transports you to a world of arena rock and produces
spectacular, thick, meaty tones.