Mounting hardware kit sold separately. Recommended for 3/4 Ton and 1 Ton Applications.Simple bolt on installationAdds new life to old springs and reduces body roll; variable rate leaves do not affect ride when unloadedHigh quality spring steel leavesRaised height and spring rate can be varied depending on adjustment of outer upboltsLoad pro 3500 pounds level load capacity has 4 leaf stack offering maximum in carrying capacity. Mounting kit is sold separately backed with a lifetime warranty. Adds new life to old springs and reduces body roll. The variable rate leaves do not affect ride when unloaded. It has a simple bolt on installation. Consists of high quality spring steel leaves. The raised height and spring rate can be varied depending on adjustment of outer upbolts.