REPLACEMENT XHT BLADES Extreme Hardness Toughness 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. By the way they are made in the USA! This sale is for 3 replacement XHT blades. Replaces the following OEM part numbers: CRAFTSMAN/HUSQVARNA/POULAN 137380 156468 21798 532137380 6196 6264 Center hole: 5 POINT STAR Width: 2-1/4" Thickness: .165" Length: 17-3/8" 3 NEEDED ON 50" DECKS Â· Disclaimer: We list model numbers and part numbers for references only. At times the same model may take different parts based on serial number breaks or manufacturers specifications. We list all the specifications on the part (size, width, length, thickness, etc.) and YOU must know what is needed on YOUR application. We canÂt possibly make it more known as to what you are receiving when you purchase.