A&I XHT 21", 15/16X11/16" HL Mower Blade (Single) - B1MA2433,1 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. (1) blade for 21" cut walk-behind. C to C 2 1/2" Center Hole 15/16" x 11/16" Length 21" Outer Hole 5/16" Thickness .134 Type Medium Lift - Notched Width 2-1/4" Crossed From: A-42-0641 MTD/ CUB CADET/ WHITE 335-677 STENS 335677 STENS 6450 ROTARY 742-0641 MTD/ CUB CADET/ WHITE 7420641 MTD/ CUB CADET/ WHITE 942-0641 MTD/ CUB CADET/ WHITE 9420641 MTD/ CUB CADET/ WHITE 98-098 OREGON 98098 OREGON This is an aftermarket product, not an OEM. A physical address must be provided, NO P.O. BOXES. Thanks for looking!