This little gadget, MSR's MIOX water scrubber is a military-grade water purifier that will generate sodium hypochlorite from adding salt. The resultant chemical will kill anything in the water, including Giardia if treated for four hours. You put pure salt and a few drop of water in the cap, screw on the cap, push the button, and get the option of choosing the strength of the solution for the amount of water needing treatment. The device is highly reliable and easy to use and a great adjunct to Jim Humble's protocol. As a water purifier, it has no filtering capability and the more turbid and cloudy the water, the more ineffective as bugs can hide in the crud. So consider using a simple filter to descum the water supply but realize this mighty pen-sized device will kill everything.