XHT 16-5/8" Mower Blade - B1KU1028 XHT (Xtreme Hardness & Toughness) blades feature a unique steel that incorporates boron, carbon, manganese, and other materials that ensure its strength. The blades are heat treated with the patented and independently tested Marbain heat-treating process. This process makes the blades 25% - 40% harder than standard lawnmower blades, making them the longest-lasting, safest, and most impact resistant lawnmower blades on the market. Center Hole 11/16" Length 16-5/8" Replaces K5575-34330 Type High Lift Width 2-1/2" Crossed From: K5182-71840 KUBOTA K518271840 KUBOTA A-K5575-34330 KUBOTA K5575-97530 KUBOTA K557534330 KUBOTA K557597530 KUBOTA SW11944 A & I MEGA-CROSS 1913-2220 A & I MEGA-CROSS 19132220 A & I MEGA-CROSS 330-821 STENS 330821 STENS 92-047 OREGON 92047 OREGON This is an aftermarket product, not an OEM. Thanks for looking!