This is a A-R97800 Disc, Brake PN: R97800Main Description As Following : A-R97800 Disc, Brake P.N: R97800 Inside Diameter: 2.551"Outside Diameter: 15.118"Thickness: .278" Crossed From: WN-R97800 , , WNR97800 , Found in Section & Models : Transmission & Rear Axle > Brake Disc and Plates, John Deere TRACTOR: 4450 (Power Shift SN 028981> / Quad Range SN 015486>) Associated Items : New Also This is An Aftermarket Product And : High Quality Afternaket Shipped from Both US and Canada