The LoadLifter 7500 XL Ultimate Air Spring Kit gives your Silverado or Sierra 3500 Chassis Cab the support it needs for heavy towing and hauling. With large 7-inch double-convoluted air springs, it levels up to 7, 500 pounds and does it with less air pressure than similar systems. The air springs adjust from 5 to 100 PSI to match your load, helping to reduce squat, sway, bottoming out, and poor headlight aim. It also features an internal jounce bumper that absorbs shock and protects the system, even at zero PSI. The underframe design works with most in-bed hitches and installs easily with included instructions. Specs: Up to 7, 500 lbs. of leveling capacityAir springs fully adjustable from 5-100 PSI for precise controlInstructions IncludedReplacement Air Spring: 58120Weight: 44.75lbWidth: 17inDepth: 10inHeight: 12inUnderframe kit designed to work with most in-bed hitchesFeatures Air Lifts limited lifetime warranty, with a 60-day ride satisfaction guarantee Fitment Note: Fits Chassis Cab (Commercial Chassis) only, will not fit standard pickup.• Silverado• Sierra 3500 Chassis Cab Internal jounce bumper absorbs shock & can be safely run with zero PSI Application type: Rear Kit Levels your vehicle when towing or hauling | Air Lift LoadLifter 7500 XL Ultimate Air Spring Kit