The Mishimoto 92-99 BMW 3 Series Aluminum Coolant Expansion Tank is a high-quality, direct-fit replacement for the stock plastic tank. This tank is made from lightweight aluminum and features a durable, wrinkle black powder-coated finish. It is designed to increase coolant capacity and reduce coolant temperatures while providing a sleek, stylish look. It also includes a magnetic drain plug for easy maintenance. This tank is backed by Mishimoto's lifetime warranty for ultimate peace of mind.