Genuine OEM Audi Engine Coolant Hose with Regulator, part number 8V0121124. This critical component is responsible for circulating coolant throughout the engine cooling system and regulating its flow to maintain optimal engine operating temperatures. It is designed to withstand high temperatures and pressures. Constructed from durable rubber and integrated with a plastic regulator, it weighs approximately 0.14 kg. Choosing a genuine OEM coolant hose ensures correct routing geometry, material resistance to engine fluids, and precise regulator calibration for reliable cooling system performance.