A&I XHT 18-1/8", 3/8" Mower Blade (Set of 2) - B1MU2603,2 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 36" cut. Center Hole 3/8" Length 18-1/8" Thickness .134 Type Low Lift Width 2" Crossed From: 3447 ROTARY 39311NOMA/AMF/DYNAMARK 54884 NOMA/AMF/DYNAMARK 56821 NOMA/AMF/DYNAMARK 7-06724 PRIME LINE 706724 PRIME LINE 782965 NOMA/AMF/DYNAMARK 8685 NOMA/AMF/DYNAMARK 8685 39311 NOMA/AMF/DYNAMARK 8685-39311 NOMA/AMF/DYNAMARK 868539311 NOMA/AMF/DYNAMARK This is an aftermarket product, not an OEM. A physical address must be provided, NO P.O. BOXES. Thanks for looking!