I put my fire number (street address) on both the front of my camper a couple of years ago.
I read that overseas there is quite a problem with trailers being stolen, so this was a suggestion they made to make it more difficult for someone who is driving off with your camper. These are the reflectorized letters that you can purchase at any hardware store. And since the number is right on your drivers
license, it is hard to forget it. I also painted this same number on the roof in 6 inch letters. Of course if you feel you are be followed by the CIA via black helicopters, or aliens, this modification might not be for you.