This is a A-R90331 Pulley, Fan Drive (Double Groove) PN: R90331Main Description As Following : A-R90331 Pulley, Fan Drive (Double Groove) P.N: R90331 New 2 groove fan drive pulley fits multiple John Deere Tractor models. Crossed From: R71019 JOHN DEERE Found in Section & Models : Cooling Systems > Water Pumps, Pulleys, & Gaskets, John Deere TRACTOR: 4050 (TRACTOR SN: < 006509), John Deere TRACTOR: 4250, John Deere TRACTOR: 4450 Associated Items : New Also This is An Aftermarket Product And : New 2 groove fan drive pulley fits multiple John Deere Tractor models.