Dodge Timing Belt Pulley, Dyna-Sync, Taper-Lock Bore Type, 1/2 to 1-11/16 in Bore Dia, 3.83 in Outside Dia, 3.581 in, 30 Grooves, 3/8 in Pitch, 3/4 in Face Width, 3.83 in Flange Dia, 3.06 in Hub Dia, 1/2 in Hub Projection, 1610 Bushing Synchronized and no-slip transmissionNo lubrication requiredApproximately 98% efficiency can obtainedLow maintenanceVirtually no backlashConstant linear velocity8.5:1 drive ratioEasy On/Off operationFlange design standard on drive size