Genuine OEM Volkswagen Chain Tensioner, part number 03C109507Q. This part is vital for the engine's timing system, applying constant pressure to the timing chain to prevent slack and maintain accurate valve timing. It is typically located within the engine's timing cover. Constructed from durable cast metal, this tensioner weighs approximately 0.098 kg. Opting for genuine OEM ensures the correct tensioning force and material quality for reliable timing chain operation.