All cartridges in the Seagull IV and First Need ranges employ the "Structured Matrix" chemical-free technology. The scientifically designed technology enables you to drink water safely, any where in the world! Tested and certified by the NSF, meets EPA standards for removal of bacteria viruses, and protozoa, plus organic and inorganic chemical and aesthetic contaminants at the "purification" micron level (0.4 microns absolute/0.1 nominal) while protecting against water related disease. Travel in extreme regions and turn the most infested water supplies into safe, refreshingly delicious drinking water. Seagull IV and First Need purifiers are used by the UN Peace Keeping forces in natural disaster areas. They are used in over 40 countries and for over 30 years.
Use this water purifier catridge with First Need Trav-L-Pure Water Purifier