Genuine OEM Volkswagen Coolant Hose, part number 5N0121447H. This hose is essential for transporting coolant between various engine components, playing a critical role in regulating the engine's operating temperature. It is situated at position 4 in the provided diagram. Constructed from durable materials resistant to heat and coolant, this genuine OEM hose ensures reliable fluid transfer and system longevity. Proper fitment and material integrity are vital for preventing leaks and maintaining optimal cooling performance.