This is a A-199643C1 Sprocket, Driving PN: 199643C1Main Description As Following : A-199643C1 Sprocket, Driving P.N: 199643C1 Dim A (1): 30 ToothDim B (2): 7.585" O.D.Dim C (3): 1.139" Hex Hub Crossed From: AM199643C1 , , AV101373 VAPORMATIC Found in Section & Models : Headers/Platforms/Feeder House > Corn Head Parts, Case-IH HEAD, CORN: 1043, Case-IH HEAD, CORN: 1044, Case-IH HEAD, CORN: 1064, Case-IH HEAD, CORN: 1083, Case-IH HEAD, CORN: 1084, Case-IH HEAD, CORN: 900 SERIES Associated Items : New Also This is An Aftermarket Product And : Dim A (1): 1.139" Hex Hub Outside Diameter: 7.585" Teeth: 30