This is a A-40X30 Sprocket PN: 40X30Main Description As Following : A-40X30 Sprocket P.N: 40X30 Hub Required: XInside Diameter: 2"Outside Diameter: 5.057"Teeth: 30 Crossed From: WSS104030 , , 20004030 , , 20004030 , , 3016-0158 , , 6713-50713 JOHN DAY , 673-S80403000 , , 673S80403000 , 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: 5.057" Teeth: 30