Whenever the metal divot things in jeans touch my skin I get a rash. At least I used to, I might have out grown it, but I haven't let those things near my skin in long time.
It took the doctors forever to figure out what it was. Finally, before I started the 8th grade a doctor figured out what was causing the rash. At first we just kept those divot thingies covered up with tape just to be sure, but now I just make sure that there's a barrier of cloth between the metal and my skin.