"Enjoy quick and easy filtered water when you need it with the Platypus GravityWorks 4L Water Filter System. Designed to provide up to 4L of filtered water in just 2-1/2 minutes without any cumbersome pumping, this lightweight system utilizes gravity to deliver safe water for several people. This lightweight 10.75-oz. system includes a capable filter that meets all EPA and NSF guidelines for the removal of Bacteria and Protozoa, including Giardia, Cryptosporidium, E. coli, Salmonella, and Cholera. The dual-bag system also doubles as a handy water transport solution, carrying up to 8L. Made of Platypus' taste- and BPA-free food grade liners, the GravityWorks' 2 bags feature Platy zip opening for easy filling/emptying. The system's hollow-fiber filter traps particles down to .2 microns and backflushes in just 4 seconds for easy maintenance. 9.5""L x 3.25""W bags. Filters up to 1,500L per filter. Manufacturer model #: 3135. Easy-to-use, pump-free water filtering system 4L of filtered water in just 2-1/2 minutes 2 taste- and BPA-free food grade liners Hollow fiber filter traps particles down to .2 microns Meets all EPA and NSF guidelines for the removal of Bacteria and Protozoa Doubles as a water transport solution: holds up to 8L"