Genuine OEM Audi Engine Coolant Hose, part number 8J0121109B. This essential hose is a key component of the engine cooling system, responsible for circulating coolant to regulate engine temperature. It connects the coolant expansion tank to other parts of the cooling circuit, ensuring efficient heat transfer. The hose weighs 0.066 kg and has dimensions of approximately 0.204 m in length, 0.063 m in width, and 0.048 m in height. Using a genuine OEM coolant hose guarantees the correct material composition for resistance to heat and pressure, along with precise routing geometry to prevent kinks and leaks, ensuring reliable engine cooling.