This chain transmits mechanical power from the drive sprocket to the slat-and-flight assembly that moves crop material up the inclined feeder housing. It engages with the sprocket teeth and pulls the flights across the feeder floor, delivering the crop mat to the threshing cylinder. A worn or stretched chain causes flight misalignment, reducing feed rate and increasing the risk of slug feeding at the cylinder entrance. The manufacturer machines the link pitch and pin diameter to match the original sprocket geometry, so the chain seats correctly without accelerated sprocket wear. On installation, verify the chain tension per the service manual and replace the sprockets if they show hooking or wear.