RockJock's rear bump stop kit for TJ Wrangler and LJ Unlimited vehicles is the only bump stop on the market that incorporates coil spring retainers to positively attach the top and bottom of the coil springs to the vehicle. This kit extends the top and bottom bump stop impact points the necessary amount for a 4 in. lift. Constructed of quality polyurethane components and billet aluminum spacers, these bump stops mount inside the coil springs. This is a kit for the rearend of the vehicle only.