This hexagonal V-belt transmits power from the drive pulley to the driven pulley in the harvester's drive system. Its hexagonal profile allows it to engage pulleys from both sides, which is necessary for serpentine routing where the belt wraps around multiple components. A worn or stretched belt slips under load, causing the driven components to run below their intended speed and reducing throughput. The manufacturer machines the belt to match the original cross-section and length, so it seats correctly in the pulley grooves without requiring tensioner adjustment beyond the standard range.