Prefabricated building components of metal, namely, ceiling boards and floor boards; metal covers, namely, metal vent covers for HVAC ducts; materials for coverings of metal, namely, metal shingles; metal sheets for coverings; connectors of metal for coverings and covering beams in the nature of structural joint connectors of metal; zinc-coated steel sheets; metal ridgeboards for coverings; brackets of metal for use in construction and the assembly of roof coverings; materials of metal for co...