SET OF SIX OREGON GATOR BLADES - 396629 OREGON Blades 396629 is 21", .505 Round center hole. Made in USA. Tungsten carbide is "fused" into the blade - creating an ultra-hard layer at the cutting edge and increasing the time between sharpening. High-lift: The aggressive blade angle increases air flow to push debris up-and-out for superior bagging or side discharge. Replacement for major brand Bush Hog. Bush Hog: (CZ) Commercial Series, (EC) Estate Commercial, (HS) Home Series, (PZ) Professional Series, EFM600, FE21B, FTH600, FTH720, M2254, M2254K, M2255, M2354, M2355, M2554, M2555, M2661, M2672, M2673, M2761, MTH-600, MTH-720, PRO52, PRO61, RDTH 60, RFM 60, TD-1500, TD-1700, TH48, TH60, TH72, ZT-18 18HP, ZT-180 18HP, ZT-22 22HP, ZT-220 22HP, ZT-220W 22HP, ZT-22W 22HP, ZT-230 30HP, ZT-25 25HP, ZT-250 25HP, ZT-30D 30HP. Bush Hog Part Mapping: 50029159, 50034299, 50055707, 50056493, 82324, 823242, 823243, 95754. This is an Aftermarket part. Thanks for looking!