The ALF-Prefilter filters out arsenic, lead and fluoride up to 99%.
It also filters hydrogen chloride, hydrogen sulfide, carbonyl sulfide, carbon dioxide, alcohols, and ethers.
Prefilters need to be placed into housings. The Prefilters, themselves, are designed to last about a year. You can purchase the housings separately on the Water Filters & Prefilter Systems page.
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