The Eibach Pro-Kit for 00-05 BMW 325xi/330xi Sedan is a performance suspension upgrade designed to improve the handling and ride quality of your vehicle. This kit includes a set of four progressive-rate lowering springs, which reduce body roll and improve cornering capabilities. The kit also includes four dampers, which provide a smoother ride, reduce body roll, and improve the overall stability of the car. The Pro-Kit is designed to be an easy, bolt-on installation and is backed by a million-mile warranty.