Proper maintenance is important for safe, efficient plowing. Always replace worn or uneven cutter blades for effective plowing. The cutter blade is the detachable blade bolted to the bottom of the plow. It takes most of the "wear and tear" during plowing and it's designed to be removed and replaced for maintenance. This reversible cutter blade is designed exclusively for the UniPlow Heavy-Duty 60" One-Box ATV Plow Systems - Extreme Max part numbers 5500.5094 (UniMount), 5500.5109 (Polaris 570 Sportsman Mount), 5500.5112 (Cam-Am Outlander Mount).