Ideal for backpacking, backcountry camping, and emergency preparedness, the bladder features a wide mouth cap that allows for fast and easy filling and a convenient carry handle. It rolls up for easy packing and doesn't add much weight to your bag (3.75 ounces for 1-gallon and 4.5 ounces for 2-gallon). It's easy to set up a gravity based filtering system with the Water Reservoir and either the PointOne Squeeze Filter or MINI water filter. First fill the reservoir with water from any source a lake, stream, faucet, etc. and then hang the bag with the MINI connected below it (via the included hose) to let gravity do its work. Water will flow through your water filter to produce fresh, clean water for drinking and cooking. Since 1984, Sawyer has used technological advancements to create products that keep you outdoors from the backcountry to the backyard including insect repellents for both skin and clothing, water filters for camping and emergencies, and sun protection.