Oregon 590-669 Mulching Blade, Gator G5, 17" Center hole: 11/16" X-Tended Cutting Length optimizes the cutting efficiency with each revolution. Tungsten carbide is fused into the blade  creating an ultra-hard layer at the cutting edge and increasing the time between sharpening. Gator Mulcher provides cleaner, more efficient cutting performance that can eliminate the need to bag, saving time and hassle. Replaces major brand: Dixon. High-lift: The aggressive blade angle increases air flow to push debris up-and-out for superior bagging or side discharge.