Righting' an overturned vehicle, especially one that is not badly damaged, has become a science. When a commercial vehicle ends up on its side there will often be little clearance to slide lifting strops underneath it. Even if this can be done, the use of strops can cause further damage and are often not the right way to start a lift. To solve this problem, recovery operators often use air bags to at least start the lift of the casualty. A number of bags can be used and this spreads the load throughout the length of the vehicle. Only a low pressure is used, which means in the event a bag is punctured, it just gently deflates and does not explode. Once the casualty is above 45 degrees, a normal winch can be used to finish the job.