QualityParts From Oregon That you can depend on. Center hole: 7/8": Requires 2 blades for 42" cut; High-lift: The aggressive blade angle increases air flow to push debris up-and-out for superior bagging or side discharge; Enhanced hardening to keep the blade sharper and more durable; Made to exact OEM specifications; Replaces major brand: Murray; Oregon Equipment Parts 97-008 Blade Murray 492418Ma 21-1/4