Holders of non-metallic materials for liquid gas tanks; non-metallic fuel tanks; non-metallic regulating valves (other than parts of machines or level controlling in tanks); non-metallic regulators (valves) (other than parts of machines or level controlling in tanks); plastic fuel tanks (other than parts of vehicles); plastic water tanks; rainwater tanks of plastic; tanks made principally of plastics materials and for use in industry; tanks, not of metal nor of masonry; water storage tanks of plastic; holders of non-metallic materials for liquid gas tanks; non-metallic fuel tanks; non-metallic regulating valves (other than parts of machines or level controlling in tanks); non-metallic regulators (valves) (other than parts of machines or level controlling in tanks); plastic fuel tanks (other than parts of vehicles); plastic water tanks; rainwater tanks of plastic; tanks made principally of plastics materials and for use in industry; tanks, not of metal nor of masonry; water storage tanks of plastic