Paratech's Maxiforce Air Lifting Bags work on a simple yet proven law of physics. For each pound (psi) of air pumped into the lifting bags, that force is multiplied over the bag’s entire surface area, creating tons of force. Paratech's Lifting Bags have a 1” maximum thickness which permits us to lift in areas where no other lifting devices can be used. A compressed air cylinder is used, and a regulator reduces the air pressure to 118 psi. The regulator reduces the incoming pressure to 118 psi from the 2200 psi air cylinder. The air then passes through the air supply hose. By pressing a valve, air begins to flow. The safety relief guards against over inflation of the airbags. The gauges will show how much pressure is in the airbag. Air passes through the safety hose, which has double locking couplings and connects the controller and airbag. Air enters the airbag. When air is forced into the center of the bag, lifting begins. The more air you place in the bag, the more the bag expands.