Max Clutch Lube System has revolutionized the standard centrifugal clutch by adding special features that will extend the life of ordinary centrifugal clutches. Has grooved bushing for grease retention and ground sleeve with hole for grease. Has a built-in internal key. No set screws required. Bore 3/4″, Chain type No. 35, No. of teeth 12.Sprocket on clutch can be mounted either inboard or outboard.