The ICON Vehicle Dynamics Lexus GX Rear Coil Spring Conversion Kit consists of billet aluminum bump stop spacers, polyurethane coil spring isolators, and all necessary hardware for installation. The height of the included bump stop spacers has been optimized for use with ICON rear shock absorbers to allow for maximum compression travel and full utilization of ICON shock absorbersÆ ôbump zonesö for increased suspension performance.