A&I XHT 18-1/2", 13/16" Mower Blade (Single) - B1SN3014,1 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. Type High Lift - Notched Crossed From: 13482 ROTARY 1737252 MASSEY FERGUSON 1737252 SIMPLICITY 1737252 SNAPPER 1737252 YAZOO/ KEES 1737252A SIMPLICITY 1737252A SNAPPER 1737252A YAZOO/ KEES 1737252AYP SIMPLICITY 1737252AYP SNAPPER 1737252BM SIMPLICITY 1737252BM SNAPPER 1737252BM YAZOO/ KEES 1737252BMA SIMPLICITY 1737252BMA SNAPPER 1737252BZ SIMPLICITY 1737252BZ SNAPPER 1737252BZ YAZOO/ KEES 1737252BZYP SIMPLICITY 1737252BZYP SNAPPER 1737252BZYP YAZOO/ KEES 1737252MA SNAPPER 1737252MA YAZOO/ KEES 1737252SM SIMPLICITY 1737252YP SIMPLICITY 1737252YP SNAPPER 99-133 OREGON 99133 OREGON This is an aftermarket product, not an OEM. A physical address must be provided, NO P.O. BOXES. Thanks for looking!