General business items: Investment in industrial enterprises (specific projects to be declared separately); Domestic trade; Import and export of goods and technology. Licensed business items: Production and sales of insulating materials and optoelectronic materials; Technical research, development, manufacturing and sales of general mechanical equipment and accessories, metal products, railway vehicle parts, photovoltaic equipment and components; Manufacturing and sales of rubber and plastic products, hardware electrical appliances, electronic products, office supplies, ceramic products, electrical cables, stamping parts, rubber and plastic seals, machine accessories, solar photovoltaic components, and aluminum alloy products.