Genuine OEM Audi Alternator Drive Belt, part number 077903137AE. This multi-ribbed belt is a crucial component of the engine's accessory drive system, responsible for transmitting power from the crankshaft to the alternator, power steering pump, and other auxiliary components. It ensures continuous power generation and proper functioning of these systems. This durable rubber belt weighs 0.32 kg and measures 0.55m in length. Choosing a genuine OEM drive belt guarantees the correct length, tension, and material composition for optimal grip and resistance to wear, heat, and stretching, which are essential for reliable accessory operation and preventing unexpected breakdowns.