One New Aftermarket Replacement XHT Lawnmower blade XHTXtreme Hardness Toughness blades are 2540 harder than standard lawnmower blades Bene Fits of the HXT blade are sharper and longer lasting cutting edges More resistance to bending Tighter tolerances in the aftermarket vs OEM XHT blades also offer greater impact toughness1 blade for 30 cut rear engine rider Punched for our B1SB1131 high lift deflectorC to C712Center Hole1116Hole Diameter10625