This is a A-ACSPROCKET1 Sprocket w/ 1" Hole PN: ACSPROCKET1Main Description As Following : A-ACSPROCKET1 Sprocket w/ 1" Hole P.N: ACSPROCKET1 Dim A (1): 3.000" diaDim B (2): 12 tooth Crossed From: AV103219 VAPORMATIC , SW01504 , Found in Section & Models : Headers/Platforms/Feeder House > Corn Head Parts, Gleaner HEAD, CORN: SEVERAL Associated Items : New Also This is An Aftermarket Product And : Dim A (1): 3.000" dia Dim B (2): 12 tooth