... osmosis technology to purify running water, combine with filter and absorb system, can efficiently get rid of ... Process:1st stage PPF: Remove suspension of more than 5m dia. in water, colloid, particle, mud, etc.2ndstage Granular ... remains, halide, etc.4th stage RO membrane: Thoroughly remove the bacteria, heavy metal, salt bad mineral substance ... and keep it fresh. drinking water filter for home use