XHT 20-3/8", 27/32", Mulch Mower Blade (Set of 4) - B1MU2616,4 Replacement XHT Lawnmower blade. XHT(Xtreme Hardness & Toughness) blades are 25-40% harder than standard lawnmower blades. Benefits 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 toughness. (2) blades for 40" cut. Center Hole 27/32" Length 20-3/8" Thickness .134 Type Medium Lift Width 2-3/4" Crossed From: 335-016 STENS 335-479 STENS 335016 STENS 335479 STENS 456251 MURRAY 456251M MURRAY 56251 MURRAY 56251E701 MURRAY 56251E701MA MURRAY 6145 ROTARY 7-06415 PRIME LINE 706415 PRIME LINE 97-004 OREGON 97004 OREGON A physical address must be provided NO PO BOXES. Thanks for looking!