Heavy-Duty Pulley Clutch For 5 HP rating, ID: 3/4 ", For 5 HP compactors, Ball bearing, Keyway: Grooved, One piece steel pulley and drum, heavy-duty, Fits A or B belts, 3/16" keyway, 5 3/8" OD pulley. Fits Models: Replaces Part Numbers: Noram 40028 Stens Part Number: 255-715