19 CONSTRUCTION MATERIALS NOT MADE OF METAL, NAMELY CONSTRUCTION COMPONENTS, ESPECIALLY IN THE FORM OF NON-METAL PLATES AND BLOCKS AND NON-METAL SPACERS AND PROTECTION RAILS; SHEATHING COMPONENTS; SEMI-FINISHED GOODS IN THE FORM OF LACES AND STRIPS; PARTITIONS, SLUICE GATES, PEDESTALS, COVERING BOXES, CHANNELS, SOFFITS, BEAMS, STEPS, CHUTES, FRAMES, SUBSURFACE STRUCTURES FOR PLUMBING AND ELECTRICAL FACILITIES NOT MADE OF METAL; PLACE HOLDERS, NOT MADE OF METAL, FOR ARMATURES SUBSEQUENT INSTALLATION; CONDUITS AND PIPE BOXES NOT MADE OF METAL; WALL, CEILING AND FLOOR MATERIALS, NOT INCLUDING ACOUSTICAL PRODUCTS, AND MOSAIC TILES NOT MADE OF METAL; AND PLASTER