QualityParts From Oregon That you can depend on. Center hole: 6 point start, 5/8": Tungsten carbide is “fused” into the blade – creating an ultra-hard layer at the cutting edge and increasing the time between sharpening; X-Tended Cutting Length™ optimizes the cutting efficiency with each revolution; Gator Mulcher® provides cleaner, more efficient cutting performance can eliminate the need to bag, saving time and hassle; The aggressive blade angle increases air flow to push debris up-and-out for superior bagging or side discharge; Replacement for major brand: Cub Cadet; Oregon Equipment Parts 591-938 Blade Cub Cadet Gator G5