ReadyLIFT 1.5 inch Add-A-Leaf for the rear of 2007-2018 Chevy Silverado and GMC Sierra 1500 trucks. Heavy Duty steel - the same construction as the factory rear springs. These rear add-a-leafs insert into your existing rear spring pack to provide an additional 1.5 inch of rear lift. Ideal for when the additional rear lift is required. Works well by itself or when teamed with a pair of ReadyLIFT rear lift blocks