X-Green Ceramic Water Filtration Manufacturing Corp.s N-FS-3-Bio-Alk features a triple-tube system to filter out substances larger than 0.9 micron. The first tube contains a ceramic cartridge with KDF, CaSO3, bio-stone and fiber carbon. The second features alkaline stone, silver carbon and more bio-stone while the third is a 0.1-micron ceramic cartridge with alkaline stone, silver carbon, bio-stone, fiber carbon and nanosilver. Replacement cartridges and other media products are also available.www.X-green.commay@x-green.com