Drive gear has the standard six bolt 5/16-24 bolt pattern with the 1.250" register on the gears. Gears will fit GM, Mooneyham, Hampton, BDS, Blower Shop, Kuhl, Bowers and most all other superchargers that use GM size shafts in the rotors of the supercharger.
Customer must have ability to time the rotors in the blower if purchasing these. Gears do not simply slide on and gears are timed. If unsure how to time the gears best left to a shop that specializes in blower repair.