QualityParts From Oregon That you can depend on. Center hole: 5/8": Aggressive blade angle increases air flow to push debris up and out for superior bagging or side discharge; Enhanced mulching for bagging and discharge efficiency; Stays sharp and durable; Major brand replacement: John Deere and Bobcat; Requires 3 for 61" cut; Oregon Equipment Parts 93-011 Blade Bobcat 21In[506]