This multi-ribbed belt transmits power from the engine crankshaft to the fan drive pulley. It sits in the front accessory drive system, maintaining tension across the pulleys to keep the cooling fan at its designed rotational speed. A worn or glazed belt slips under load, reducing fan speed and causing the cooling system to run above its normal temperature range. The belt is manufactured to the original profile and cord tension specifications so it seats correctly in the pulley grooves without requiring shimming or a different tensioner setting.