This V-belt transmits power from the engine pulley to the driven pulley in the drive system of the parent combine. It is a two-rib belt that sits in the pulley grooves and transfers torque to the auxiliary shafts that power the threshing and cleaning assemblies. A worn or glazed belt slips under load, causing a drop in rotor speed and uneven crop flow through the concave. The belt is manufactured to the original cross-section profile so it seats fully in the pulley grooves without bottoming out, which maintains the correct tension range for the automatic tensioner. On installation, check pulley alignment and adjust the tensioner to the specified deflection.