To those who prefer self-contained water filtration systems this is the system for you. Simply scoop water and continue the adventure.For a lightweight and fast solution to clean water in the backcountry or for international travel the Sawyer Water Treatment Bottle is the way to go. Fill up the bottle directly from a lake stream or creek and drink instantly without any residual chemical tastes. This water treatment bottle comes with Sawyer's ONE MILLION GALLON GUARANTEE. The Hollow Fiber Membrane filter physically removes particles 99.9% of bacteria and 99.9% of Protozoa down to 0.1 micron absolute in size including Giardia Salmonella and Cryptosporidia. There's such little resistance that you could even squeeze the water out of the bottle. And you can adapt the standard 63mm cap to your existing bottle. Bottle weight: 5 oz. Bottle capacity: 32 oz.