Filtering up to 1.75 liters a minute without any pumping, the high-capacity GravityWorks Water Filter System filter is one of the easiest and fastest ways to get filtered water in the backcountry. The GravityWorks is ideal for bigger backpacking groups or basecamps suppling filtered water for drinking, washing up, cooking, and cleaning. 

• 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.