This left-side tooth is the replaceable ground-engaging component on a rotary harrow. It mounts to the harrow rotor via a pin and cotter pin, and the matching right-side tooth is installed opposite it on the same rotor. The tooth breaks and mixes the soil as the rotor turns; a worn or broken tooth reduces tillage depth consistency and increases draft load on the tractor. The original manufacturer's geometry matches the rotor pocket so the tooth sits at the correct working angle without shimming. When replacing, use the specified pin and cotter pin and verify the tooth is fully seated in the rotor pocket before operation.