The Sawyer Squeeze Filter is the lightest and most versatile filtration system on the market. With a total field weight of 3 ounces and ability to roll up, it takes up virtually no space in your pack. This product includes 1 pouch ( 1 L ) that can be reused hundreds of times. Simply fill up the pouch at a lake, stream or river, screw the filter directly onto the pouch and 1) Squeeze the bag and filter water into your water bottle or container of choice, 2) Drink directly from the filter which has a built in push pull cap for on/off functions, 3) Attach the filter onto most threaded water bottles including 2 liter bottles. Kit includes: 1 - Lightweight Durable Collapsible Pouch ( 1 L pouch), Sawyer 0.10 Absolute Micron Hollow Fiber Membrane Screw On/Off Water Purifier, Replaceable Pop Up Drinking Spout, Cleaning Syringe. Life Expectancy: 1 Million Gallons Guaranteed.