filters for drinking water; household and industrial installations for drinking water filtration, consisting of filters and housings therefor, all sold as a unit; ceramic elements for the conditioning of drinking water; and ceramic elements for the removal of impurities from drinking water

[FILTER BED MATERIALS,] CERAMIC LIQUIDFILTERS, [AND LIQUID STERILIZING APPARATUS COMPOSED OF A STORAGE TANK LINED WITHCHLORINE RESISTING MATERIAL AND FITTED WITH A CLOTH STRAINER, STERILIZING AGENT FOR THE CONTENTS OF THE TANK, A COMBINEDDECHLORINATING AGENT AND A BED OF] STERILIZING MATERIAL COMPOSED OF SAND [OR ACTIVATED CARBON WHEREIN OR WHEREON SILVER HAS BEEN DEPOSITED AND LIQUID FLOW CONNECTIONS BETWEEN THE TANK AND UNIT AND ADRAW-OFF CONNECTION THE UNIT.]