Genuine OEM Porsche Coolant Expansion Tank, part number 95810615100. This expansion tank serves to maintain the correct coolant levels and manage pressure within the engine's cooling system, accommodating expansion and contraction of the coolant. It is an integral part of the cooling system assembly. Constructed from durable, coolant-resistant plastic to ensure a long service life. Genuine OEM expansion tanks are designed to withstand the thermal and pressure cycles of the cooling system, ensuring reliable operation.