Genuine OEM Volkswagen Air Filter, part number 4M0133837. This filter is designed to remove contaminants from incoming air, ensuring a clean air supply for the engine and optimal combustion. It is a crucial part of the air intake system for engine longevity. The filter media and its precise fit within the housing are essential for effective filtration. Genuine OEM air filters offer the correct filtration efficiency and airflow characteristics for peak engine performance and protection.