Center Cap Not Included. Use Oem Center Cap. Dim A (1): 16.5" Diameter Dim B (2): 7/8" 36 Spline Hub Dim C (3): 2.50" Id For Cap Dim D (4): 36 Splined Tapered Hub Replaces: Ar78405 Al28457; John Deere Compact Tractor 3120