SET OF 12 A&I Mower Blade XHT - B1KU1024,12 XHT (Xtreme Hardness & Toughness) blades feature a unique steel that incorporates boron, carbon, manganese, and other materials that ensure its strength. The blades are heat treated with the patented and independently tested Marbain heat-treating process. This process makes the blades 25% - 40% harder than standard lawnmower blades, making them the longest-lasting, safest, and most impact resistant lawnmower blades on the market. Dim E (5): XHT Dim F (6): 3 Blades Used For 60" Cut Center Hole: 1.125" Length: 20.500" Replaces: K5647-34330, K5647-34340 Thickness .250" Type High Lift Width 2.500" Replaces: B1KU1023 SUNBELT CANADA K5647-34340 KUBOTA K564734340 KUBOTA Crossed From: K5647-34330 KUBOTA K5647-34340 KUBOTA K564734330 KUBOTA K564734340 KUBOTA K5668-34350 KUBOTA K566834350 KUBOTA 11558 ROTARY 92-049 OREGON 92049 OREGON Models: Kubota FRONT MOUNT MOWER: F2880 (with RCK60-F36 mower) (Qty: 3) Kubota FRONT MOUNT MOWER: F3680 (with RCK60-F36 mower) (Qty: 3) Kubota LAWN/GARDEN TRACTOR: SEVERAL Kubota MOWER DECK: RCK60-F36 (Qty: 3) Kubota MOWER DECK: RCK60P-21Z (Qty: 3) Kubota MOWER DECK: RCK60P-28Z (Qty: 3) Kubota MOWER DECK: RCK60P-331Z (Qty: 3) Kubota ZERO-TURN: ZD21 (with RCK60P-21Z mower) (Qty: 3) Kubota ZERO-TURN: ZD25 (with RCK60P-28Z mower) (Qty: 3) Kubota ZERO-TURN: ZD28 (with RCK60P-28Z mower) (Qty: 3) Kubota ZERO-TURN: ZD321 (with RCK60P-331Z mower) (Qty: 3) Kubota ZERO-TURN: ZD326 (with RCK60P-331Z mower) (Qty: 3) Kubota ZERO-TURN: ZD331 (with RCK60P-331Z mower) (Qty: 3) This is an aftermarket product. Thanks for looking!