Mota Performance A70404 Aluminum Crankshaft Pulley Double Groove 6.63" Diameter Constructed of billet aluminum Machined finish Except Corvette and early truck with factory water pumps CNC Machine balanced Billet Aluminum construction Quality Corrosion Resistant Clear Anodized Machined finish Except Corvette and early truck with factory water pumps Light weight design improves throttle response For best belt alignment use all the same brand pulleys