A personal water filter that is great for backpacking, camping and emergency kits. Filters 264 gallons to 0.2 microns (no pumping, no chemicals). Meets U.S. EPA drinking water standards. Removes 99.9999% of bacteria (E. coli, etc.) and 99.9% of protozoa (Giardia, Cryptosporidium, etc.) Made with BPA free materials. Small and lightweight enough to carry easily (9"x1" and 2 oz.). A great portable filter!