A filter will safely reduce levels of contaminant bacteria and parasitic protozoa in drinking water, while a purifier will also reduce waterborne viruses. Both purifiers and filters may remove chemical contaminants although this is less common with filters. Pure Hydration products are all technically purifiers in that they remove bacteria parasitic protozoa, and viruses. However, the miniaturised ICE° Cap is only recomended for use with treated municipal water, whereas such as the aquapure traveller can be used with any non-salt water contaminated drinking source.