Set of 24 blades. Marbane hardened steel holds edge longer than standard steel blades. Note PLEASE make sure this is the correct center hole size before ordering. 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. […]