Genuine OEM Volkswagen A/C Refrigerant Hose, part number 4F0260740B. This hose is a vital component of the air conditioning system, designed to transport refrigerant between system components under high pressure. It is marked as number 10 in the diagram. Genuine OEM hoses are manufactured with specific material compositions to prevent refrigerant permeation and are pre-formed to ensure correct routing geometry, preventing kinks and vibration-related failures.