Manufacturing, installation, and sales of railway rolling stock parts, specialized tooling equipment and parts for rail transit, metallurgical, coking, and mining machinery equipment and parts; manufacturing, processing (excluding electroplating), and sales of sheet metal products; sales of metal materials (excluding production scrap metal materials and rare precious metals), industrial electrical appliances, and chemical products (excluding toxic, hazardous, flammable, explosive, and other goods restricted or prohibited by the state); mechanical equipment design and technical consulting services; leasing of premises and mechanical equipment.