The ZeroWater ZR-001 Replacement Water Filter Cartridge uses a patented five stage dual ion exchange filter system. It removes chlorine, dust, iron, sediments, silt, rust, sand, lead, and all the dissolved salts. The ZeroWater ZR-001 Replacement Water Filter Cartridge is the only filter that meets the FDA required TDS levels of purified water, 000-010ppm. The filter cartridge has a five stage water purification system. At the first stage water is made to pass through an activated carbon infused micron cloth, then through multiple layers of activated carbon and oxidation reduction alloy, then distributor to maximize contact time, then a comprehensive Ion Exchange takes place, and finally a non-woven membrane for removing fine particles.