High-Volume 10-inch Dual Stage Portable Water Filter System PortaWell® is the best choice for a portable water filter system in off-grid or emergency situations. It filters water up to 10X faster than other portable water filter systems. It offers true two-stage water filtration system, and with a number of commercially available and industry standard 10-inch filters, you can mix-and-match for just about any situation. The PortaWell® system goes beyond manual pumping and the inefficiencies of relying on gravity alone to produce drinkable water from available surface water. It is designed to accept filters that remove 100% of cysts including giardia, cryptosporidium, and 99.99% of pathogenic bacteria (including cholera, typhoid, coliform, chlorine, metals, and volatile organic chemicals).