The Bilstein B3 90-97 BMW 3 Series Replacement Rear Coil Spring is an aftermarket suspension component designed to replace the original rear coil spring in BMW 3 Series vehicles manufactured between 1990 and 1997. This high-performance spring is designed to provide improved ride comfort and handling, as well as increased stability and cornering ability. The spring is made from high-grade steel for maximum durability and is corrosion-resistant for long-term use. The spring is also designed to be easy to install and comes with all the necessary mounting hardware.