Genuine OEM Audi Coolant Hose with Quick Release, part number 4F0121055P. This hose is designed to transport engine coolant, playing a crucial role in the vehicle's thermal management system by circulating fluid to and from the radiator. It features a quick-release mechanism for secure and efficient connection and disconnection. Positioned as part of the engine cooling system, it connects directly to the radiator. Measuring approximately 0.45 meters in length and weighing about 0.508 kg, this hose is engineered for specific routing and pressure. Using a genuine OEM coolant hose ensures correct material resistance to heat and chemicals, precise routing geometry, and reliable quick-release functionality, preventing leaks and maintaining cooling system efficiency.