TeraFlex SpeedBump bumpstops are an innovative composite bumpstop system designed for high-performance JK Wrangler applications. The true progressive nature of the SpeedBump bumpstop allows for the reduction of suspension compressing impacts and the associated harsh bumpstop bottoming. The absorption of harsh impacts experienced off road or even on a poorly maintained highway will reduce the risk of axle housing bends as well as provide an increased ability to maintain vehicle control. TeraFlex SpeedBumps feature performance tuned closed-cell nitrogen charged microcellular polyurethane technology providing a true progressive bumpstop that will not fade or dissipate under extended heavy use. Microcellular polyurethane technology is not affected by temperature extremes, and retains thermal and sub-zero temperature flexibility. The Delrin acetal resin polymer shaft is self-lubricating to allow thousands of continuous cycles without wear or abrasion. The external shaft seal further prolongs shaft life by wiping and cleaning the shaft to prevent contaminants from entering the SpeedBump housing. The maintenance free SpeedBumps require no custom adjustment or tuning. The simple bolt on installation requires removal of the factory bumpstop bell (front applications only) no welding is required. This kit includes two front SpeedBump and two rear SpeedBump bumpstops, front adjustment spacers, and front lower bumpstop strike pads.