I never use a filter. I use these to treat water from racing the Tour Divide to climbing in the 3rd world. I have never gotten sick even when sharing the stream with a herd of peruvian cows.
I see people with filters getting sick. all it takes is one drop of contaminated water...and there seems to be plenty of that when filtering. Yes, a filter can be faster when you need water right away, but proper planning usually prevents that.
Ultralight tablets provide fresh drinking water anywhere you go. Effective against viruses, bacteria, giardia and cryptosporidium. Fresh tasting water-no unpleasant taste. Easy-to-use tablets. Meets EPA purification guidelines. Purification method: Chlorine Dioxide tablets. Output: 1 tablet treats 1 qt. of wat