This flail is a pivoting steel component that mounts on the threshing drum of a combine harvester. It strikes the crop material against the concave to separate grain from the straw and chaff. Each flail is part of a matched pair; the two flails in a pair are selected to have as close a weight as possible and are installed on opposite sides of the drum. After all flails are mounted, the threshing drum must be balanced. When reconditioning the drum, replacing the entire set of flails prevents shaft wobble and maintains correct drum operation, which directly affects the service life of the cooperating components. The mounting hardware includes a bolt, nut, and washer.