Center Hole Size. The OregonĀ® GatorĀ® G6T 396-730 lawn mower blade is enhanced with carbide. This heavy duty blade is designed for commercial applications and built to withstand rough conditions with top performance and longevity. Fused with carbide for added tough cutting exterior. Superior mulching and bagging with blade angle to increase air flow. Greater width and thickness extends blade life. Major brand replacement: John Deere.