Genuine OEM Audi Additional Coolant Cooler, part number 5Q0121251HD. This component is designed to provide supplementary cooling capacity for the engine coolant, helping to maintain optimal operating temperatures. It is positioned as an auxiliary unit within the engine cooling system, typically located below the main radiators. Weighing 0.99 kg, this cooler ensures efficient heat dissipation. Choosing a genuine OEM cooler guarantees precise fitment, optimal performance, and the durability required for effective thermal management.