OVERVIEW Eliminate truck sag, sway and bottoming out with ALPHA HD PRO air bags / air helper springs from Pacbrake, the only brand with inch-thick corrosion resistant end caps and 20 support wires for maximum strength and durability. PRODUCT DESCRIPTION >> Designed for durability and performance, the ALPHA HD PRO Series comes with Jounce Bumpers/Bump Stops, a flexible polyurethane bumper inside the bag that prevents bottoming out, which could damage your air springs, and allows you to run your bags at 0 psi when unloaded for factory ride comfort. >> Perfect for those that want the peace of mind of having an internal bumper and covet the ride comfort of being able to run without air when not towing. >> For those that desire maximum bag travel, a great benefit when offroading, towing and launching boats, or for those that constantly need to lower their rear to pick up trailers, consider our HP10206 ALPHA HD air bag. >> 5,000 lbs of load leveling capacity. Never exceed manufacturer's recommended Gross Vehicle Weight Rating.