Genuine OEM Volkswagen Vent Hose, part number 2Q0121447H. This hose is a vital part of the cooling system, facilitating the release of air to prevent pressure accumulation. By allowing air to vent, it helps maintain optimal operating pressure within the cooling system, ensuring efficient heat transfer and preventing damage. The hose is made from durable, coolant-resistant materials. Using genuine OEM parts ensures precise fitment and material integrity for long-lasting performance.