HART has replacement blades for its mowers with a 20-inch deck. Due to regular use, the blades may get dull over time, making your mower less efficient. To keep your HART lawn mower running smoothly and reduce cutting time, change the blades with genuine HART replacement blades. This blade is an OEM (Original Equipment Manufacturer) product, so you can be sure it will work with your 20-inch HART 40V Push mower.