This is a A-RBW12 W Hub PN: RBW12Main Description As Following : A-RBW12 W Hub P.N: RBW12 Dim A (1): 1-5/8"Dim B (2): 1-13/16"Dim C (3): 7/16"Dim D (4): 1"Bore: 1/2" roundKeyway: 1/8" X 1/16" Crossed From: WSH20008 , , 20020008 , , 20020008 , , 3016-0107 , , 6713-57313 JOHN DAY , 673-S80020300 , , 673S80020300 , Found in Section & Models : Chains/ Sprockets/ Pulleys/ Hubs > Hubs, (Miscellaneous) (UNDEFINED): SEVERAL Associated Items : New Also This is An Aftermarket Product And : Dim A (1): 1-5/8" Dim B (2): 1-13/16" Dim C (3): 7/16" Dim D (4): 1" Bore: 1/2" round Keyway: 1/8" X 1/16"