The Sawyer One Gallon Gravity System is a lightweight, robust solution for filtering large quantities of water. With threads on both sides, you can now screw the push pull cap onto the MINI for easy on/off functionality while filtering with this easy to use One Gallon Gravity System. The Dual Threaded MINI Filter is also compatible with the cleaning coupling for backwashing (included in kit). The hollow fiber filter removes: Bacteria, Protozoa, E. Coli, Giardia, Vibrio Cholerea, Salmonella Typhi, Leptospirosis. Filter water for a group in as little as 7 minutes with a Sawyer Gravity System. Highly portable, these systems are ideal for scouts, small groups, and aid during emergencies. Just allow gravity to do the work. FeaturesThis System Includes the Dual Threaded MINI FilterRemoves 99.99999% of Bacteria and 99.9999% of Protozoa and CystsHas a Wide Mouth for Fast, Easy FillingIs Lightweight, Weighing 8.3 ounces with all the Included Components