This is a A-138775A1 Pulley, Driven Knife, Wobble Box PN: 138775A1Main Description As Following : A-138775A1 Pulley, Driven Knife, Wobble Box P.N: 138775A1 Dim A (1): 10.375" ODDim B (2): .93" IDReplaces: 114388A1 Crossed From: AM138775A1 , , 114388A1 CASE-IH , 300-C138775 , , 300C138775 , Found in Section & Models : Headers/Platforms/Feeder House > Grain Head Parts, Case-IH HEAD, CUTTING PLATFORM: 1010 (SN JJC0200001-JJC0300000; JJC0300001-JJC03, Case-IH HEAD, CUTTING PLATFORM: 1020 (SN JJC0215001-JJC0227000; JJC0315001-JJC03 Associated Items : New Also This is An Aftermarket Product And : Inside Diameter: .93" Outside Diameter: 10.375" Replaces: 114388A1