Genuine OEM Volkswagen Coolant Hose, part number 5C0122101R. This hose transports coolant between engine components and the radiator to regulate engine temperature. It is positioned as part 20 in the diagram. Made with materials designed to withstand high temperatures and pressures within the cooling system. Genuine OEM hoses are manufactured to exact specifications for a perfect fit and reliable operation, crucial for preventing engine damage due to overheating.