This is a A-H100778 Sprocket, Straw Walker Driven PN: H100778Main Description As Following : A-H100778 Sprocket, Straw Walker Driven P.N: H100778 Dim A (1): 49 teeth, 50 chainDim B (2): 10.090" OD, 2.877" ID Crossed From: AV104202 VAPORMATIC , WN-H100778 , , WNH100778 , Found in Section & Models : Separator Area > Separator Sprockets and Sheaves, John Deere COMBINE: 6620, John Deere COMBINE: 6622 Associated Items : New Also A-JD-O-OMH111330, A-JD-O-OMH120048 And : Dim A (1): 49 teeth, 50 chain Dim B (2): 10.090" OD, 2.877" ID