Blade Width – 2.50. Thickness – 0.250. Blade Length – 20-9/16. Center Hole Size – 1-1/8. Air Lift – 1-1/8. The OregonĀ® 91-438 replacement lawn mower blade is made to the exact OEM specification for optimum performance. Our blades are individually straightened and hardened to provide a consistent, cleaner cut and increase blade longevity. Requires 3 blades for 60 cut. For B1550, B1750, F2560E, F3060, G1900, G2000 Models. Major brand replacement: Kubota. Fits the Following Models. B1550, B1750, F2560E, F3060, G1900, G2000. Replaces the Following Blades.