The Aries AF-20-3690 Fluoride Reduction Filter Cartridge uses the specifically designed ResinTech® SIR-900 media to effectively remove fluoride and other contaminants across a broad range of pH and pressures. Fluoride naturally finds its way into water sources from the composition of the surrounding rock and earth. Further unnatural fluoride can contaminate water as runoff from aluminum and fertilizer factories which can be dangerous. A level of fluoride greater than 4.0 mg/L or 4.0 ppm, set by the EPA, can cause negative health side effects. The scientifically engineered ResinTech® SIR-900 media uses a fabricated aluminum oxide to safely and efficiently remove excess fluoride. Use the Aries AF-20-3690 Fluoride Reduction Filter Cartridge to remove harmful levels of fluoride from your drinking supply to enjoy cleaner and safer water.