Genuine OEM Audi Engine Timing Sprocket, part number 059109570F. This precision-machined metal gear is a vital component within the engine's timing assembly, designed to engage with the timing chain. Its function is to synchronize the rotation of various engine components, such as the crankshaft and camshafts, ensuring precise valve timing and optimal engine performance. Using a genuine OEM sprocket guarantees exact tooth profiles and material hardness, which are crucial for reliable engine operation and preventing premature wear of the timing system.