From MXR...
"Guitarists of all styles will dig the familiar late-Sixties/ early-Seventies crunch delivered by the new MXR Classic 108 Fuzz. We've taken the guts of our BC-108 loaded Fuzz Face, placed them in a more pedal-board friendly shape, and added the modern conveniences of a battery door, optional AC operation, and true bypass with LED. The Buffer switch eliminates the audible oscillation caused when some wah-wahs are placed in front of a Fuzz Face. The Classic 108 Fuzz comes in a heavy-duty Phase 100-sized box with a sweet hammertone turquoise finish."