QualityParts From Oregon That you can depend on. Center hole: 5/8": Requires 3 blades for 60" cut; High-lift: The aggressive blade angle increases air flow to push debris up-and-out for superior bagging or side discharge.; Superior mulching for bagging and discharge efficiency; Enhanced hardening to keep the blade sharper and more durable; Replacement for major brand: Gravely; Oregon Equipment Parts 91-239 Blade Gravely 20-1/2In[405]