A&I XHT 21", 5/8" Notch Mower Blade (Set of 6) - B1FE1061,6 Replacement XHT Lawnmower blade. XHT(Xtreme Hardness & Toughness) blades are 25-40% harder than standard lawnmower blades. Benefits of the XHT 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. (3) blades for 61" cut. Fits new iCD decks. Center Hole 5/8" Length 21" Thickness .250 Type Medium Lift - Notched Width 2-1/2" Crossed From: 5101755 FERRIS 5101755 SNAPPER This is an aftermarket product, not an OEM. A physical address must be provided, NO P.O. BOXES. Thanks for looking!