Sales of intelligent unmanned aerial vehicles; manufacturing of mechanical and electrical equipment; manufacturing of metal materials; manufacturing of coal-fired flue gas desulfurization and denitrification equipment; manufacturing of special equipment for environmental protection; software development; information system integration services; information system operation and maintenance services; sales of communication equipment; sales of network equipment; sales of information security equipment; sales of cloud computing equipment; sales of Internet equipment; sales of artificial intelligence hardware; sales of optical communication equipment; sales of digital video surveillance systems; sales of audio equipment; sales of batteries; sales of refrigeration and air-conditioning equipment; sales of fire-fighting equipment Sales; sales of doors and windows; sales of metal products; production, processing, and sales of: fiberglass products, bridges, grilles, central air-conditioning terminal products, cooling towers, pipes, fans, dust removal and desulfurization flues; sales: building materials (excluding hazardous chemicals), decorative materials (excluding hazardous chemicals), chemical raw materials (excluding hazardous chemicals), auto parts, motorcycle parts, hardware, Jiaodian, general machinery, communication equipment, metal materials, instruments and meters, measuring instruments, computers and auxiliary equipment, cultural supplies, general machinery and equipment.