Genuine OEM Volkswagen Tensioner Pulley, part number 05C109479B. This component is crucial for maintaining the correct tension on the timing belt, ensuring accurate engine timing and preventing belt slippage. It is typically located within the engine's timing belt system. The pulley is made from durable materials designed for long service life. Genuine OEM parts are vital for timing components as they guarantee the precise tolerances and material integrity required for the engine's critical timing functions.