This is a A-50X27 Sprocket PN: 50X27Main Description As Following : A-50X27 Sprocket P.N: 50X27 Hub Required: XInside Diameter: 2"Outside Diameter: 5.723"Teeth: 27 Crossed From: WSS105027 , , 20005027 , , 20005027 , , 3016-0198 , , 6713-52213 JOHN DAY , 673-S80502700 , , 673S80502700 , 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: 5.723" Teeth: 27