The EVO MFG 2.5" JL Boost Suspension systems lift your 2018+ Jeep Wrangler JL 2.5"s. The JL Boost kits are specifically designed to lift your JL and maintain factory spring rate, compliance and ride quality while having the option of retaining factory shocks, maintaining full wheel travel with use of shock extensions (part number EXT kits) or without shock extensions to allow for use of your choice of aftermarket 2/2.5" lift shocks. In using rigid steel coil spacers we maintain the factory ride quality without effecting or lowering spring rate like the alternative compressible plastic or poly urethane spacers. EVO MFG JL Boost kits are available in multiple configurations to suit your needs and budget and are upgradable down the road. These Boost kits will fit up to a 37" tires on Rubicon Model JLs or 35" tires on Sahara and Sport/S.Stage 1 kits includes all the necessary parts to lift your JL 2.5"s. Stage 2 kits includes Stage 1 components as well as EVO MFG Enforcer JL Front Lower Adjustable Control Arms to allow for caster adjustments. Stage 3 Kits includes stage 2 components as well as EVO MFG Enforcer rear upper adjustable control arms for rear pinion angle adjustment. Stage 4 kits includes stages 1 components with all 8 EVO MFG Enforcer control arms for full front and rear axle adjustments. *All part number "EXT" kits include front and rear shock extensions. Maintaining factory spring rate and shocks.