John Deere Original Equipment Pulley - AUC20589 Belt Drive Pulley Part Specifications: Belt Section (ALPHA) HB, Effective Diameter (MM) 101.6000, Groove Width (MM) 14.2800, Angle (ALPHA) 34, Bore Size (MM) 8.0000, Key Width (MM) 0.0000, Length (MM) 20.5000, Material (ALPHA) H22, Note (A) There is more information on the engineering blue print that is not shown in detail here. Fits the following John Deere models: Mower: 7700A, X330, X350, X350R, X354, X370, X380, X384, X390, X394, X584. This is an O.E.M. John Deere part. John Deere Original Equipment Pulley - AUC20589 Belt Drive Pulley Part Specifications: Belt Section (ALPHA) HB, Effective Diameter (MM) 101.6000, Groove Width (MM) 14.2800, Angle (ALPHA) 34, Bore Size (MM) 8.0000, Key Width (MM) 0.0000, Length (MM) 20.5000, Material (ALPHA) H22, Note (A) There is more information on the engineering blue print that is not shown in detail here. Fits the following John Deere models: Mower: 7700A, X330, X350, X350R, X354, X370, X380, X384, X390, X394, X584. This is an O.E.M. John Deere part.