Lowering Kit The H&R 15-18 BMW X5 M F85 Sport Spring Lowering Kit is designed to provide a more aggressive stance and improved handling for your BMW X5 M. This kit includes four progressive rate springs that are designed to provide a lower center of gravity and improved cornering capabilities. The kit also includes four bump stops and four dust caps. Installation is quick and easy and no special tools are required. This kit is a great way to improve the performance of your BMW X5 M.