The ProOne G2.0 Water Filter is NSF/ANSI certified and independently lab tested by an EPA-approved lab. Our ProOne filters qualify as a microbiological water purifier and helps remove harmful contaminants including heavy metals, VOCs, lead, fluoride, pesticides, herbicides, chloramines, bacteria, pharmaceuticals, microplastics and much more. Our water filters retain beneficial minerals like calcium for a healthier glass of water. Silver impregnated ceramic composite helps prevent bacteria growth and self-sterilizing. Uses AquaMetix advanced media for heavy metals, arsenic, fluoride, bromine and other contaminants. Does not contain any alumina like other brands use in their water filters. Fits most competitive gravity water fitler systems such as Berkey. Designed to remove pathogenic bacteria and cysts, in addition to having exceptional chemical and contaminant removal properties. The majority of pathogenic (disease causing) bacteria and cysts are larger than one micron. The ProOne G2.0 water filter element is controlled so that it will remove Cysts greater than 1 micron, and bacteria greater than 0.7 microns. Reccomended replacement for the 7" size: up to 10 months per pair. Fits the Propur Nomad and Big systems.