This gear drives the chain conveyor that moves grain from the cleaning shoe to the unloading auger. It mounts on the conveyor shaft and engages the chain at a pitch that matches the original drive sprocket. A worn gear causes chain slip or uneven conveyor speed, which reduces throughput and can jam the elevator. The gear is machined to the same tooth profile and bore tolerance as the original assembly, so it seats on the shaft without modification. On installation, verify the chain tension and alignment to prevent accelerated tooth wear.