This is a A-AH145983 Sprocket, Row Unit, LH, 25 Teeth / 60 Chain PN: AH145983Main Description As Following : A-AH145983 Sprocket, Row Unit; LH, 25 Teeth / 60 Chain P.N: AH145983 Dim A (1): 25 ToothDim B (2): 6.367" O.D.Dim C (3): 1.130" Hex Hub Crossed From: AV103497 VAPORMATIC Found in Section & Models : Headers/Platforms/Feeder House > Corn Head Parts, John Deere HEAD, CORN: 692 (SN <705250), John Deere HEAD, CORN: 693 (SN <705437), John Deere HEAD, CORN: 694 (SN <705420), John Deere HEAD, CORN: 892 (SN <705500), John Deere HEAD, CORN: 893 (SN <705984), John Deere HEAD, CORN: 894 (SN <705667) Associated Items : New Also This is An Aftermarket Product And : Dim A (1): 25 Tooth Dim B (2): 6.367" O.D. Dim C (3): 1.130" Hex Hub