This is a A-RE15018 Pulley, Dampener PN: RE15018Main Description As Following : A-RE15018 Pulley, Dampener P.N: RE15018 A-RE15018 Pulley, Dampener P.N: RE15018 Crossed From: AMRE15018 , , R71021 JOHN DEERE , R71022 JOHN DEERE , WN-RE15018 , , WNRE15018 , Found in Section & Models : Engine Parts > Crankshafts, John Deere COTTON PICKER: 9950, John Deere COTTON PICKER: 9960, John Deere COTTON PICKER: 9965, John Deere COTTON PICKER: 9970, John Deere GRADER: 770A (W/ 6466 Engine), John Deere GRADER: 770AH (W/ 6466 Engine), John Deere GRADER: 770B (Engine SN <499999 W/ 6466 Engine), John Deere GRADER: 770BH (Engine SN <499999 W/ 6466 Engine), John Deere GRADER: 772A (W/ 6466 Engine), John Deere GRADER: 772AH (W/ 6466 Engine), John Deere GRADER: 772B (Engine SN <499999 W/ 6466 Engine), John Deere GRADER: 772BH (Engine SN <499999 W/ 6466 Engine), John Deere INDUSTRIAL/CONSTRUCTION: 664D (W/ 6466 Engine), John Deere TRACTOR: 4050, John Deere TRACTOR: 4055, John Deere TRACTOR: 4250, John Deere TRACTOR: 4255, John Deere TRACTOR: 4450, John Deere TRACTOR: 4455 (North America Edition), John Deere TRACTOR: 4555 Associated Items : New Also A-JD-O-OMRW16854, A-JD-O-OMRW16854 And : Outside Diameter: 9.862"