The Vaico Coolant Expansion Tank - V100979 is a high-quality replacement part for a vehicle's cooling system. It is designed to hold excess coolant that is expelled from the radiator due to heat and pressure. This expansion tank is made from durable materials and is built to withstand the extreme temperatures and pressures of the engine's cooling system. It is a direct fit for specific makes and models of vehicles, ensuring easy installation and proper functioning. This product is crucial for maintaining the proper level of coolant in the vehicle, which is essential for keeping the engine cool and preventing overheating.