Dodge Single Groove Sheave, Arm Type D2, Taper-Lock Bore Type, 7/16 to 2 in Bore Dia, 9-3/4 in Outside Dia, 9.38 in (A)/9.76 in (B) Pitch Dia, 1 in Face Width, SDS Bushing, 1.57 in Overall Length, For Use With: A-B Cross Section Belts, Cast Iron Isolates shock loads and vibrationMisalignment capabilityLow maintenanceNo lubrication requiredQuiet operation motors, etc. are normally at a higher db level than V-drivesEfficiency of 95% is typical