Sales and maintenance, production and processing of high and low voltage electrical appliances, high and low voltage complete sets of equipment, electrical accessories, power automation products, instruments and meters, and electronic components; wholesale of building materials, wires and cables, engineering machinery equipment and accessories, mechanical and electrical products and equipment, automobile and motorcycle accessories, metal materials, Wujinjiaodian (excluding electric bicycles), and labor protection supplies , Purchasing and sales agency; research and development, technical consulting, and technical services of office automation equipment, communication equipment, intelligent network control system equipment, and computer software and hardware; power technology research and development and technical consulting services; power engineering construction; self-operated and agent import and export of various commodities and technologies, except for commodities and technologies that are restricted by the state or prohibited from import and export.