Whenever I travel somewhere where the drinking water is questionable, I bring a SteriPEN and use it daily to purify water right from the tap, rather than buying bottled water. However, on a recent trip, my SteriPEN wasn’t working because I made the mistake of bringing some old rechargeable batteries which weren’t up to the task. This was a classic example of being too dependent upon technology. I realized that if I had gotten sick, or just desperately needed some water in the middle of the night, I would’ve been screwed.

So, lesson learned, and the latest addition to my first aid travel kit is a few Katadyn Micropur Water Purification Tablets. One tablet dropped in a quart or liter of water will kill viruses and bacteria in 15 minutes, Giardia in 30 minutes and Cryptosporidium in 4 hours. While it’s certainly not as fast as the SteriPEN, it’s nonetheless an excellent backup which adds practically nothing to your pack weight.