This is a A-40V13 Sprocket PN: 40V13Main Description As Following : A-40V13 Sprocket P.N: 40V13 Hub Required: VInside Diameter: 1 1/8"Outside Diameter: 2.329"Teeth: 13 Crossed From: WSS104013 , , 20004013 , , 20004013 , , 2827-37627 JOHN DAY , 3016-0141 , , 6713-49913 JOHN DAY , 673-S80401300 , , 673S80401300 , Found in Section & Models : Chains/ Sprockets/ Pulleys/ Hubs > Sprockets, (Miscellaneous) (UNDEFINED): SEVERAL Associated Items : New Also This is An Aftermarket Product And : Hub Required: V Inside Diameter: 1 1/8" Outside Diameter: 2.329" Teeth: 13