The Bilstein B3 04-10 BMW X3 Series Replacement Rear Coil Spring is an OEM-style replacement part designed to replace the original rear coil spring on 2004-2010 BMW X3 series vehicles. This spring is constructed of high-quality steel and is designed to provide a smoother ride and better handling. It also features a corrosion-resistant coating for added protection against the elements. This spring is an ideal choice for restoring your BMW X3 to factory specifications.