JK specific tuned for high-speed performanceUsed in our 2.5 inch Sport ST2, 3 inch Sport ST3, 3 inch Alpine CT3, and 3 inch Alpine CT3 Outback Overland, 4 inch Alpine CT4, and 6 inch Alpine CT6 suspension systemsFoam Progressive Bump Stops simply pop-in to the existing factory locationsReplaces factory foam bump stopsPerformance-tuned closed-cell nitrogen charged microcellular polyurethane technologyAbsorbs large impact energy progressively during compression to prevent bent axle tubesPrevents damage to suspension components, shock absorbers, and fendersQuiet movement and function (no pad-slap clunk)Maintains progressive nature during all conditionsWill not fade or dissipate under extended heavy useUnaffected by temperature extremes - retains flexibility in thermal or subzero tempsResistant to all types of environmental conditions (mud, salt, sand, dust, etc.)Subzero temperature flexibility reduces fatigueCompatible w/ all suspension systems that retain factory axle spring mounting locationsMaintenance-free, all composite constructionSimple bolt-on installationPatented technologyFits:JK Wrangler (2-door)JK Wrangler Unlimited (4-door)Includes:Rear foam Progressive Bump Stops (2.5-3.5 inch Lift) - pairRear Upper SpeedBump Bump Stop Cup Extension - pair0.75 inch SpeedBump Bump Stop Strike Pad Kit - Rear Lower (part number 1954600)All necessary hardware