Add some additional reliability and engine bay styling with the Mishimoto Subaru WRX/STI Aluminum Coolant Expansion Tank. Stock coolant expansion tanks are prone to failure after years of constant temperature variations. The Mishimoto tank is constructed from durable, TIG-welded aluminum with barbed fittings for optimal durability and longevity. This expansion tank provides a 50% increase in capacity compared to the stock unit. It features a polished finish that will look great in your engine bay, and it and matches the Mishimoto Performance Aluminum Radiator! The Mishimoto Coolant Expansion Tank is engineered for perfect fitment in the 2002-2007 WRX and the 2004-2014 STI! As with all our products, this expansion tank includes the Mishimoto Lifetime Warranty, ensuring superior product quality and craftsmanship.