Air Lift LoadLifter 5000 Air Spring Kits feature 2-ply reinforced commercial-grade bellows to be mounted between the spring and frame. They can be inflated from 5 to 100 psi to level loads up to 5,000 lbs. on any kind of heavy load vehicles. The kits include bellows, air lines, fittings, brackets, mounting hardware, and instructions. The average installation time is about two hours.