Genuine OEM Audi Engine Chain Sprocket, part number 057109570A. This precision-machined component engages directly with the engine's timing chain, transferring rotational motion to ensure synchronized operation of engine components. It is an integral part of the engine's chain drive system. Weighing 0.135 kg, this genuine OEM sprocket is manufactured to exact tolerances, which is essential for maintaining precise engine timing and preventing catastrophic engine damage.