Magnetic bumper stickers

I don’t put bumper stickers on my cars for the same reason I don’t put tattoos on my skin. I’m committment challenged. Today’s clever sticker will seem dated and lame in a week. And I’ll play hell getting the thing off my car. So no bumper stickers. But every time look at a photo of the rear “bumper” on the Land Rover (looks more like part of the frame to me but everyone calls it the bumper) I think, “What a good spot for a bumper sticker”

Then I thought of magnetic bumper stickers. Sure enough, they make them and the made a couple for me.

Barb asked what would keep someone from taking this. And do what with it?