This rubber cover shields the upper section of the threshing unit, preventing crop material and debris from wrapping around or lodging against rotating components. It mounts along the concave housing and acts as a flexible barrier between the threshing drum and the stationary frame. A torn or missing cover allows straw and chaff to accumulate, which can cause belt slippage or localized overheating. The cover is formed to match the original profile so it seats against the housing without gaps. On installation, verify that the fastening points align with the existing holes and that the cover does not contact the drum at any point during rotation.