Dodge Single Groove Sheave, Arm Type C3, QD Bore Type, 7/16 to 2-5/8 in Bore Dia, 18-3/4 in Outside Dia, 18.38 in (A)/18.76 in (B) Pitch Dia, 1 in Face Width, SK Bushing, 1.93 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