This is a A-1306352C1 Sprocket Assy., Main Drive PN: 1306352C1Main Description As Following : A-1306352C1 Sprocket Assy.; Main Drive P.N: 1306352C1 Dim A (1): 24 Tooth Double SprocketDim B (2): 6.153" O.D. Crossed From: AM1306352C1 , , AV100673 VAPORMATIC Found in Section & Models : Headers/Platforms/Feeder House > Corn Head Parts, Case-IH HEAD, CORN: 1054, Case-IH HEAD, CORN: 1063, Case-IH HEAD, CORN: 900 SERIES Associated Items : New Also This is An Aftermarket Product And : Outside Diameter: 6.153" Teeth: 24 Double Sprocket