Genuine OEM Audi Belt Tensioner, part number 079903133AL. This critical component is designed to maintain proper tension on the engine's accessory drive belt. It ensures consistent power transfer to various engine accessories like the alternator and power steering pump. Weighing 1.044 kg, it is constructed from durable materials for long-term reliability. Choosing a genuine OEM tensioner ensures precise spring calibration and pulley alignment, preventing premature belt wear and system failure.