A lightweight, robust solution for filtering large quantities of water, Sawyer's Gravity System with Dual-Threaded MINI filter is ideal for backpacking, backcountry camping, and emergency preparedness. Available in the 1-Gallon Gravity System (SP160) comes with one bag and a MINI. The Sawyer dual-threaded MINI water filter weighs just 2 ounces, fits in the palm of your hand, and is rated to 0.1 micron absolute filtration — removing 99.99999% of all bacteria, such as Salmonella, Cholera, Leptospirosis, and E.coli, and removing 99.9999% of all protozoa (such as Giardia and Cryptosporidium). The MINI also filters out 100% of microplastics (independent testing laboratory Hydration, LLC.; microbiological report S05-03). With threads on both sides, you can screw the push pull cap onto the MINI for easy on/off functionality while filtering. Convenient and easily packable, this single- and dual-bag gravity system doesn’t require any pumping and is perfect for camping, hunting, fishing, scouting, disaster relief, and emergency preparedness kits, as well as on adventure travel excursions where potable tap and bottled water are not easily carried or safe to drink. The 1-gallon bladders feature a wide mouth cap that allows for fast and easy filling, as well as a convenient carry handle. To set up a gravity system, first fill the reservoir with water from any source (a lake, stream, pond, glacier, kitchen faucet, etc.). Hang the bag — from a tree, the back of your pack, or hold it up with your hand — and connect the MINI to the included hose and let gravity do its work. Water will flow through the MINI to produce fresh, clean water for drinking and cooking. Sawyer Products has offered the best, most technologically advanced solutions for protection against sun, bugs, water, and injuries – everything from first aid kits developed for wilderness to point-of-use water filters that filter contaminated water to levels cleaner than U. S. bottled water.