This flail is a component of the threshing drum assembly, designed to be mounted on the drum rotor. It interacts with the concave and the crop flow to separate grain from the straw. The flail is secured in place using a screw, nut, and washer. A worn or missing flail reduces threshing efficiency and can cause uneven crop processing. The original part matches the hole pattern and mounting geometry of the factory assembly, ensuring correct positioning on the drum without requiring modification.