Never passes untreated water - An enclosed caliper (measuring device) lets you know when element needs to be replaced. Water flow lessens when it's time to clean the element. When it plugs, just brush it off and re-use! Competing filters let contaminated water reach your cup as they age. Won't crack like cheap imitations.

No chemicals - Disease-causing germs and cysts can't get past the filter's microscopic (.2 micron) pores. Self-sterilizing; silver granules hermetically sealed in the filter core positively prevent bacteria growth and mold. Doesn't add to, detract from, or change make-up of water. No chlorine, iodine or other caustic chemicals!

EPA Registered - Removes 100 percent of algae, suspended contaminants and bacteria. Used by NATO, International Red Cross, and Wycliffe Bible Translators. Tested and praised by the U.S. Testing Company in New Jersey and Harvard University Department of Applied Sciences.

"The Katadyn pump is tough and stood up to the most exacting and continuous use. A final testimony to the efficiency of the filter is that the only occasion we didn't use it, on the journey home from the rivers to Addis Ababa, two members of the expedition contracted dysentery."
-R. Smith, Yale University, OMO River Expedition