Plastics in extruded form for use in manufacture; semi-processed plastic used in manufacturing parts for waste water clarifying installations, drinking water treatment installations, air humidifying apparatus and installations, refrigerating apparatus and installations and cooling towers, storage and seepage installations for rainwater or waste water, namely, filling materials in foil form, in the nature of polypropylene or polyvinylchloride foil other than for packing [ ; foil of regenerated...

CELLULAR FILL MATERIAL FOR USE IN GAS-LIQUID CONTACT APPARATUS FOR BIOLOGICAL TREATMENT OF LIQUIDS