This is a A-40X26 Sprocket PN: 40X26Main Description As Following : A-40X26 Sprocket P.N: 40X26 Hub Required: XInside Diameter: 2"Outside Diameter: 4.418"Teeth: 26 Crossed From: WSS104026 , , 20004026 , , 20004026 , , 2827-38927 JOHN DAY , 3016-0154 , , 6713-50513 JOHN DAY , 673-S80402600 , , 673S80402600 , 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: 4.418" Teeth: 26