2x Front Billet Upper Lift Spacers2x Front Delrin Bottom Lift Spacers2x Rear Steel Lift Blocks4x Premium Electrostatic Powder Coated U-BoltsInstallation InstructionsPrecision CNC Machined for Outstanding Performance and QualityProprietary Protective Coating to Prevent Oxidation, Corrosion & RustIncrease Ground Clearance & Install Custom Plus Sized Rims & TiresIMPORTANT: *Will fit 6-Lug / New Body Style Models Only.*This Kit is NOT compatible with 2007 Classic Models.* For Z71 / LTZ Models, rear lift height will vary depending on factory block size being replaced. Please check your truck's rear setup before ordering.*Does not fit 2019 2020 GMC Sierra Denali models with ARC Suspension / Magna-Ride / Auto-Leveling SuspensionSupreme Suspensions PRO-Billet Strut Spacers are precision CNC machined from T6 Aircraft Aluminum, then anodized black for a superior corrosion resistant finish. The SOLID single-piece construction ensures extreme compression resistance, while still being light-weight and resistant to typical corrosion associated with off-roading.For the rear of your vehicle, we are proud to introduce the New 2019 Low Weight HD Structure Steel Blocks. Using Heavy-Duty GMAW seam and fillet welding processes we reinforced it's structure with a 1/4" Thick CNC Plasma Cut Center Support Structure and a 9/16th Center Pin to ensure stability, perfect fitment and easy installation. LAB Tests have shown these blocks can withstand an astonishing load of almost 60,000 lbs with no yielding or deformation observed!We've also made sure the extended U-bolts we provide rise to expectation, being ISO 9001 certified and stamped. NOTES: An alignment is always recommended after altering the height of your vehicle.