Metal strips on exterior walls?

i am just curious, we have all of the drywall torn out of our singlewide mobile home, and all of the insulation so we can work on wiring. I noticed yesterday that every six feet or so, there is a metal strip that runs from ceiling to floor along the exterior walls. These strips are approximately six inches wide and do not seem to be supporting anything, as they are quite loose. They are firmly attached at the ceiling, and at the floor so it doesnt come out, but you can shake it with just a bare hand. They do not extend below the bottom of the trailer. What could they be?
I am positive they are not hurricane straps. My parents' mobile home has hurricane straps, and they are tighter and thinner than these things.