This is a A-R81507 Pulley PN: R81507Main Description As Following : A-R81507 Pulley PN: R81507 Found in Section & Models : Ignition & Electrical Parts > Alternators & Related Parts, John Deere FORAGE HARVESTER: 5200 (6404/6531), John Deere FORAGE HARVESTER: 5400 (6404/6531), John Deere FORAGE HARVESTER: 5440 (6404), John Deere FORAGE HARVESTER: 5720, John Deere FORAGE HARVESTER: 5730, John Deere FORAGE HARVESTER: 5820, John Deere FORAGE HARVESTER: 5830, John Deere TRACTOR: 4000 (SN: 201000 >), John Deere TRACTOR: 4020 (SN: 201000 >), John Deere TRACTOR: 4030, John Deere TRACTOR: 4050, John Deere TRACTOR: 4230 (SN: < 039567), John Deere TRACTOR: 4240, John Deere TRACTOR: 4240S, John Deere TRACTOR: 4250, John Deere TRACTOR: 4320, John Deere TRACTOR: 4350, John Deere TRACTOR: 4430, John Deere TRACTOR: 4440, John Deere TRACTOR: 4450 Associated Items : New Also A-JD-O-OMR46934, A-JD-O-OMR48273, A-JD-P-PC1116, A-JD-S-TM1006, A-SMJD203, A-FRM-JD, A-JD-O-OMR34410, A-JD-O-OMR41754, A-JD-O-OMR46934, A-JD-O-OMR48273, A-JD-P-PC1116, A-JD-P-PC859, A-JD-S-SM2039, A-JD-S-TM1006, A-MW-OP-JD4010, A-MW-S-TURBO, A-SMJD203, A-FRM-JD, A-JD-S-TM1055, A-SMJD50 And : Double Groove, (Used w/ Delco Remy Alternators) Dim A (1): EFFECTIVE DIA: 3.434" Dim B (2): GROOVE WIDTH: .500" Dim C (3): GROOVE WALL ANGLE: 36 DEGREES Bore: .67"