SET OF 3 - SUNBELT BLADE-MOWER, 17-7/8", 3/4" - B1CC1403 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. (3) blades for 50" cut. Fits Tank Commercial and ZTR Z Force. Center Hole: 3/4" Length: 17-7/8" Thickness: .197 Width: 2.5" This is an Aftermarket part. Thanks for looking!