21-inch Universal Gold Commercial Mulching Blade. Blade measures 21-inch x 2-1/4-inch with a 1-inch center hole. Includes a cover washer and 6 reducing washers in the following sizes: 3/8-inch, 7/16-inch, 9/16-inch, 1/2-inch, 5/8-inch, and 13/16-inch. Blade features sharpened cutting teeth for a cleaner, finer cut, and a centrifugal air lift design for uniform chopping distribution. Also features greater cutting surface.