3. A lighter
Even if you don't smoke, a few butane lighters and some other fire makers should be scattered throughout your equipment and clothing. The advantages of this fire starter are plain to see: they are affordable, operate one-handed, they're waterproof, and they can light hundreds of fires. And don't ever make the mistake of thinking you won't need fire in a backcountry emergency. Fire signals for help, boils water, cooks food, warms the body, lights up the darkness, and provides many other lifesaving tasks. Make sure the lighters are colorful, in case you lay it down or drop it. I had a camo lighter once—briefly.