I agree with Pete, that is what I use.  But you might think of adding a inexpencive coin battery flashlight.  A good thing about using shrink tube, if you need to add something to the necklace you don't have to start all over.
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Some people try to turn back their odometers.
      Not me, I want people to know "why" I look this way
      I've traveled a long way and some of the roads weren't paved