Wholesale of electronic components; Mechanical and electrical equipment installation services; Wholesale of instruments and meters; Wholesale of building materials and decorative materials; Wholesale of electrical equipment; Import and export of goods (except for special commodities); Wholesale of hardware products; Technology import and export; Sales of general machinery and equipment; Sales of electrical and mechanical equipment; Trade agency; Wholesale of electronic products; Manufacturing of power electronic components; Manufacture of transformers, rectifiers and inductors; Manufacturing of photovoltaic equipment and components; Manufacturing of electrical accessories, power distribution or control equipment parts; Wire and cable manufacturing; Manufacturing of insulating products; Manufacturing of industrial automatic control system devices; Manufacturing of electrical instruments and meters; Manufacturing of electronic measuring instruments; Manufacturing of components and devices of general and special instruments and meters; Energy technology research and technology development services; Engineering and technical research and test development; Technical services (excluding license approval projects); Professional contracting of electromechanical equipment installation works; Electronic product design service;