13 METALLIC FLUID-CONDUCTING TILE, METALLIC SEWER AND DRAIN PIPE, METALLIC CULVERT PIPE, LINED AND UNLINED METALLIC CONDUIT FOR STEAM AND OTHER FLUIDS, UNDERGROUND AND OVERHEAD STEAM, OIL OR HOT WATER PIPES, ENCASED AND UNENCASED INSULATED FLUID DISTRIBUTION CONDUITS, PREFABRICATED INSULATED PIPING SYSTEMS