There aren’t many companies that can say they developed an outdoor water purification device specifically for use by the US military … and took six years to be sure they got it right. MSR can make that claim and more with its new Guardian Water Purifier.
Filter systems have generally been constrained by their ability to eliminate only bacteria and Cryptosporidium (a microscopic, diarrhea-causing parasite), but not viruses. Purification systems get rid of viruses, but take longer to do so. What makes the MSR Guardian different is that it acts as both filter and purifier and is claimed to eliminate all biological threats you might find in even the dirtiest of water.
