Genuine OEM Audi Expansion Tank, part number 4S0121403B. This component is crucial for the engine cooling system, storing excess coolant and allowing for its thermal expansion and contraction as engine temperature changes. It is typically located in the engine bay, connected to the radiator and engine. Constructed from durable, heat-resistant plastic, it measures approximately 0.225m x 0.225m x 0.225m and weighs 0.85 kg. Choosing a genuine OEM expansion tank ensures precise fitment, correct pressure ratings, and material integrity to withstand temperature fluctuations and chemical exposure, preventing leaks and system failures.

Catalogue entry: CONTAINER.