This chain drives the pick-up drum on the grain harvester header. It transmits rotational force from the drum’s drive sprocket to the drum shaft, which rotates the tines that lift the crop mat from the ground onto the conveyor. A worn or stretched chain causes the drum to slip or run at an incorrect speed relative to the header, leading to uneven crop feeding and material loss at the header-to-feeder interface. The chain is manufactured to the original pitch and link count so it meshes correctly with the existing sprockets without requiring a sprocket replacement.