I happen to LOVE Loon UV Knot Sense for many things but especially for in-the-field repairs to fly lines, leaders and other stuff.

Old Sol is usually available for curing duties but that handy dandy UV light has been a welcome addition to my kit on many occasions. Unfortunately if you keep the light in a pocket like I do; that little button that turns the diminutive light on can get pressed easily draining those expensive little button batteries. You end up with a dead light when you need it most.

I tested a theory yesterday when I used up my tube of Blistex. I was pleased to find that the light fits PERFECTLY inside of an empty tube of Chap Stick or your favorite lip balm.

Get your spent lip balm tube and with the cap off and the balm cranked all the way up take out the little cup that allows the lip balm to move up and down; this will reveal the complicated guts of the lip balm machinery. Next, pop out the bottom adjuster wheel and the long spiral rod will come out with it. For the most part removing the adjuster wheel and spiral rod will leave a small hole that is way too small to cause a problem but if you want it back on just bust off the spiral rod and pop the adjuster wheel back on.

After cleaning out the left over lip balm you will have a perfect case with a tight fitting cap for the UV light that will keep the button from getting pressed which means it will work when you need it!

And if you are inclined to worry about such things; you just recycled 98% of the used lip balm tube! I'm sure there are other good uses for those little tubes too.

BTW - If you are a fan of Aveeno; their tube design doesn't lend itself to UV light cases.