Doulton selects the best filter materials to achieve the highest efficiency rating in reducing harmful parasites such as cryptosporidium and gardia (99.95% reduction). Lead and chlorine are significantly reduced, providing safe, great tasting water for your family and pets. The Doulton Ceramic filter is one of the most effective water filter systems available. It is constructed of ultra-fine ceramic with a filtration efficiency of 0.9 microns absolute. Independent testing documented that the Doulton ceramic is more efficient at reducing live cryptosporidium than conventional block carbon filters tested under similar condition. Doulton ceramic filters are proud of their certifications; *NSF certified for standards 42 & 53 (chlorine, parasite, lead, turbidity, bad taste and odor reduction). *Manufactured in accordance with the highest international manufacturing standards. ISO99002 and BS5750. *Doulton’s 0.9 micron absolute filtration efficiency exceeds the EPA requirement for Cryptosporidium (parasite) reduction.