Fluoride in drinking water is an unwanted contaminant for many of us. AlkaViva’s proprietary solution is the Fluoride Shield. This fluoride removal filter is NOT made of activated alumina or bone char and so it is not pH or temperature-sensitive. It employs the latest cutting edge technology. The Fluoride Shield reduces fluoride to very low levels in laboratory testing. For use with H2 Series Ionizers. (Rated for 500 Gals).