Z.Vex Woolly Mammoth
The Woolly Mammoth is a fuzz effect pedal, designed & produced by the Z.Vex Effects, a Minneapolis-based company that specializes in producing niche guitar and bass pedals, led by Zachary Vexter. The Woolly Mammoth is also used by the likes of Trent Reznor and Ian D'Sa of Billy Talent. The pedal used to me made using green housing but is now made with silver/aluminium housing, retaining the same paintjob. The Mammoth comes in two variants; one with a germanium circuit.
The pedal produces, what is reffered-to as, a "velcro" fuzz sound. It's built for both bass and guitar. It has four controls; Output (controls the level of the signal), EQ (sweeps between more bass or more treble), "Pinch" (a gentle gate-like effect) and "Wool" (amount of fuzz). Together with the Fuzz Factory it is perhaps one of the legendary pedals made by ZVex.
Chris Wolstenholme used the pedal ever since The Resistance and possibly earlier. It's unclear which songs he used it on but it is speculated that it's used on Time Is Running Out. It was also used in the studio, especially during the making of Drones, together with the ZVex Mastotron pedal. It's likely that it's been used on Dead Inside.