The pulley has a register on the back that fits in the dampner as well as a 2.00" male register on the front to keep your supercharger pulley running concentric. Included is grade eight mounting hardware and pulley thickness is 1.250", O.D. is 6.00" in diameter. This pulley uses six 3/8" bolt holes on a 2.782" bolt circle for mounting of supercharger pulley.
Fits 4-71 thru 16-71 roots or PSI screw superchargers.