Genuine OEM Volkswagen Coolant Hose, part number 5N0121447J. This hose is designed to transport coolant throughout the engine system, ensuring effective temperature regulation. It is identified at position 18 in the diagram. As a genuine OEM part, it is manufactured to precise specifications for a perfect fit and optimal coolant flow. The durable construction resists degradation from heat and coolant exposure, ensuring a long service life and preventing system failures.