From Gizmodo:

Every piece of these bras, t-shirts, underwear or socks is printed with the 4th amendment in metallic ink, which is apparently visible on TSA scans. The kids’ designs, which say “read the 4th amendment perverts,” are especially cute.

I’m all in favor of people keeping a copy of the Constitution on their person. I keep a Constitution in every suit jacket. However, TSA makes me take off my suit jacket when I go through security, so I suppose this is a surefire way to keep the Constitution at hand. It also comes in bra and t-shirt form.