Genuine OEM Audi Engine Coolant Hose, part number 4M0819373AL. This hose is designed to transport coolant efficiently within the engine cooling system, maintaining optimal operating temperatures. It connects various components of the cooling circuit, including the expansion tank. Made from durable, heat-resistant materials, it ensures a leak-free and reliable connection. Using a genuine OEM hose guarantees the correct routing geometry and fluid resistance, preventing premature wear and potential leaks.