This chain drives the reel on the header of a grain harvester. It transmits power from the drive sprocket to the reel shaft, controlling the reel's rotation speed as it feeds crop material into the cutterbar. A worn or stretched chain causes the reel to slip or run unevenly, leading to inconsistent crop feeding and potential plugging at the header. The chain is supplied with a connecting link for installation. On replacement, verify the chain tension matches the manufacturer's specification and that the sprockets are not worn to prevent premature wear.