Manufacturing of environmental protection special equipment; Manufacturing of dust removal technical equipment; Manufacturing of auto parts and accessories; Manufacturing of power transmission and distribution and control equipment; Sales of environmental protection special equipment; Sales of mechanical equipment; Sales of mechanical parts and components; Sales of gas, liquid separation and purification equipment; Wholesale of auto parts; Retail of auto parts; Retail of hardware products; Sales of metal tools; Sales of valves and cocks; Sales of special equipment; Sales of intelligent power transmission and distribution and control equipment; Sales of chemical products (excluding licensed chemical products); Repair of general equipment; Housing leasing; Leasing of non-residential real estate; Road freight transport of general cargo vehicles with a total mass of 4.5 tons and below (excluding network freight and dangerous goods); Technical services, technology development, technical consultation, technical exchange, technology transfer, technology promotion; Goods import and export; Technology import and export; Import and export agency