Ah, rubber bands. when I was 16 I had 4 paper routes that I delivered by car. It was one of the first motor routes in my county. I was given bags and bags of rubber bands to wrap the papers in.
I'm 51 now (you do the math but I think that's slightly over 5 years). I still have 2 bags of those rubber bands. They stay closed up in a drawer and they are perfectly fine. We use them for all sorts of stuff.
So much for the theory that they will degrade in a drawer when protected from the elements. .
Well, Chuck, the ones for the Federal Government must come from lowest bidder. Ours are crap after less than a year. The pencil erasers don't even work when brand new!
If the trailer is going to sit for a while, then I am a proponent for the covers. Just helps to protect from the elements and staves off dry rot. I tried to talk my inlaws into this along with tarping the top of their MH. But to no avail. Now the MH with only 5000 miles has dryrotted tires and they have had leaks from the skylights.
2008 Toyota Tacoma Off Road