This is a A-50X37 Sprocket PN: 50X37Main Description As Following : A-50X37 Sprocket P.N: 50X37 Hub Required: XInside Diameter: 2"Outside Diameter: 7.718"Teeth: 37 Crossed From: WSS105037 , , 3016-0208 , Found in Section & Models : Chains/ Sprockets/ Pulleys/ Hubs > Sprockets, (Miscellaneous) (UNDEFINED): SEVERAL Associated Items : New Also This is An Aftermarket Product And : Hub Required: X Inside Diameter: 2" Outside Diameter: 7.718" Teeth: 37