Blade-Mower, Xht, 20-1/2", 2-1/2" 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.(3) blades for 60" cut    Center Hole: 15/16"    Length: 20-1/2"    Replaces: Exmark: 103-6383    Thickness: .197"    Width: 2-1/2" Exmark Zero-Turn LAZER Z AC LAZER Z AS LAZER Z CT LAZER Z XP LAZER Z XS
