Sharpened 4 sides. Aftermarket lawn mower blade for Gravely commercial lawnmowers. Be sure to match the part number from the owners manual for the part you are replacing with the OEM number(s) listed below. All mower blades are sold individually, order quantity of(2) mower blades for 40" cut. Also fits the 60" deck, order(3) lawn mower blades for 60" cut.