To loose, or not to loose? That is the question?
I've lost several end caps over the years and (for me), the bungies work very well. Everyone has their own way of doing things, and if anyone want's to purchase new ones when they fly off, that's a personal choice.
I did re-read the posts on this thread and thought I'd give a better explanation of how I use my bumper.
First, I do not carry my sewer hoses in the bumper. I use to, but they became so full of pin-holes hall the time, I was buying new ones faster than I could use old ones. Something had to change. Then I realized those bumpers are nothing but rust collectors and rust has shards and shards punch holes in plastic sewer hoses. So I switched and installed a fence post style under the trailer system. When we got our Outback, it didn't work any more, so I started carrying them like this. Also, with 2 sewer outlets, I needed more connectors, Y's and stuff. This is my solution and I've never had a pin hole since:

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So that left the bumper empty. With my new Outback, I made some changes where I stored stuff, and decided to move metal rod items to the bumper instead of in the front pass-through. So I carry in the bumper a sprayer for the toilet-black tank, a pair of fireplace tongs, the wand for my trailer brush (which is actually just an extendable painter's handle, and our hot dog sticks. (yea, that thing that gets shoved down the toilet and the hot dog sticks are in the same container! Spank me!
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So I figure the movement of the trailer end back and forth causes those metal rod items to shift back and forth. If they punch up against the end cap ... well... thar she goes! Fortunately, I've not lost any contents inside the bumper.
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And yes, I am using those end caps with the self-sticking sides. But when one of those metal rods presses against it, well, .... as I found out a few weeks ago, they still come off and get lost.
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So, rather than drilling holes, scaring up the trailer, making modifications, and taking the lazy way out, I learned the bungie cords work pretty darn well keeping everything inside!
We ALL do it different. Nothing wrong with that!
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