2x Front Billet Strut Spacers2x Front Delrin Lower Shock Spacers4x Differential Drop SpacersInstallation InstructionsFITS LTZ AND Z71 MODELS ONLY. WILL NOT FIT STANDARD MODELS. Not compatible with DENALI models using ARC (Adaptive Ride Control) suspension (2019 models) Does not work with models equipped with magna-ride / auto-leveling suspensions (Sierra Denali models) Fits 6-Lug Models Only.*Will Not Fit 2019-2023 Sierra Elevation using SU4 or SU5 Differentials.Our Pro-Billet series strut spacer lift kits are precision engineered from 6061-T6 aircraft aluminum, then anodized for a superior finish. Billet aluminum is a great material for use in suspension applications as it has an immensely high strength to weight ratio along with a superior level of corrosion resistance compared to many other metals on the market. Unlike steel kits that are cut-out and welded together, our Pro-Billet kits are machined from a solid piece and will not bend or warp under even the most stressful conditions. Our Differential Drop Kit is highly recommended for 4WD model trucks with independent front suspension. This kit will lower your front differential and reduce the excess wear on CV joints and axles by correcting the driveline angle changes caused by lifting the front of your truck. Machined from billet aluminum, these spacers will never compress, making sure your diff stays put and always in the right location. This is a perfect complement for trucks with lift kits from any of our product lines, as well as vehicles with pre-existing coil spring spacer lift kits installed.NOTES: An alignment is always recommended after altering the height of your vehicle.