No pumping: Just fill the dirty reservoir, hang it, and let gravity do the hard work-yep, filtering water can be as easy as fill, hang, relax.Fast: Filters up to 1.75 liters per minute; microfilter lifetime up to 1,500 liters of water.Effective: Every microfilter is individually tested to ensure it meets all EPA & NSF guidelines for the removal of 99.9999% of bacteria and 99.9% of protozoa.Light & Compact: System weighs 11.5 oz. (326 g) and stows smaller than most 1L bottles.Group-ready: 8 liter (4.0L filtered 4.0L unfiltered) total capacity easily supplies water for groups.Field-cleanable: Microfilter can be easily backflushed in 4 seconds to maintain filter performance. Hollow Fiber Advantage: Hundreds of tiny, hollow fibers, enable the microfilter to filter water faster than traditional filter media. Easy collecting & dispensing: Collecting water is easy-simply open the top, scoop water, and close; control delivery of filtered water with hose shutoff clamp. Comes with: 4.0L Clean reservoir, 4.0L Dirty reservoir, Hollow Fiber microfilter, hoses, shutoff clamp, and storage sack.