Cloyes 9-3100-15 Original True Roller Timing Kit Ductile Iron; Or Hardened Cast Iron Cam Sprocket Sprockets Made From SAE D7003 Ductile Iron Premium True Roller Chain w/0.250 Dia. Rollers Billet Steel Induction Hardened Crank Sprocket w/3 Keyways; Plus Or Minus 4 Degrees