I don't have a great picture, but on mine for scout camp I used pipe insulation and a piece of plywood. I wrapped the insulation around the edges of the trailer, placed the cut-to-size plywood on top, then secured with 4 ratchet straps, two front-to-back and two side-to-side. Kept out dust and then kept out all the rain we had. Cost me about $25 in total. Plan to stain it to match and figure out a better attachment system. For what it was though, day before leaving, I was pleased.
The only place that I had an issue hauling my (teardrop) trailer.
Was Bryce Canyon. The lady at the entrance station (who takes her fed job way too seriously) procedes to tell me if im longer than 25ft , I need to disconnect and leave it in one of 2 parking lots.
Couldn't find a spot available. So I said F---it and went on. Later on up the canyon there was a sign. It said no trailers beyond this point.
Still kept going and never got looked at by the rangers.
This has me wondering how this 25ft is measured.???
Bumper to bumper or axle.?