Aqua Trex 5 stages RO filter is completely manufactured in Taiwan from high quality materials free of lead and cadmium. It is the best solution to drink a safe and pure water without dust, rust, sand,insects, chlorine salts, heavy metals, organic substances, gases and viruses.Sediment: Primary cartridge composed of polypropylene fibers at 5 microns precision to prevent impurities, sand, insects, algae and rust.GAC: Contains granular activated carbon which adsorbs gases that cause bad odor in water, chlorine and organic substances.CTO : Composed of carbon block to adsorb chlorine derivatives and organic substances, encapsulated in unwoven fabric at 5 microns precision to ensure the absence of impurities.R.O Membrane 75 GPD productivity reverse osmosis element with 0.0001 microns precision to eliminate salts, heavy metals, organic substances, viruses by 99 % rejection.Post Carbon: Contains active carbon from coconut shell to improve water's taste and adsorb gases and odors.