Genuine OEM Volvo Alternator Serpentine Belt, part number 30777530. This belt is crucial for transferring power from the engine's crankshaft to the alternator and other accessories, ensuring they operate correctly. It is designed for precise fitment and optimal performance within the engine's accessory drive system. The use of genuine OEM belts guarantees the correct material composition and tensioning characteristics for a long and reliable service life, preventing premature wear or failure.