Sales of mechanical parts and components; import and export of goods; import and export of technology; trade brokerage; domestic trade agent; import and export agent; sales agent; offshore trade operation; sales of bearings, gears and transmission parts; sales of gears, gear reducers and gearboxes; retail of auto parts and accessories; wholesale of auto parts and accessories; automobile sales; sales of new energy vehicles; sales of machinery and equipment; sales of metal tools; sales of machine tool functional parts and accessories ; Retail sales of motorcycles and spare parts; Wholesale of motorcycles and spare parts; Sales of pumps and vacuum equipment; Sales of building materials; Sales of metal materials; Sales of metal products; Wholesale of hardware products; Retail sales of hardware products; Sales of special instruments for teaching; Sales of teaching models and teaching aids; Sales of daily necessities; Sales of daily necessities; Sales of clothing and apparel; Sales of clothing accessories; Sales of plastic products; Sales of chemical products (excluding licensed chemical products) Sales of paper products; sales of non-metallic minerals and products; retail sales of cosmetics; sales of household products; sales of outdoor products; wholesale of stationery; wholesale of sporting goods and equipment; wholesale of shoes and hats; sales of first-class medical devices; sales of second-class medical devices; sales of lubricants; sales of rubber products; sales of high-quality synthetic rubber; sales of bio-based materials; sales of leather products; sales of leather; sales of communication equipment; sales of arts and crafts and gifts Sales of instrument supplies (except ivory and its products); information consulting services (excluding licensed information consulting services); leasing of machinery and equipment; leasing services (excluding licensed leasing services); office equipment leasing services; leasing of non-residential real estate; socioeconomic consulting services; Internet sales (except for the sale of goods requiring licenses); sales of electronic products; sales of optical instruments; sales of instruments and meters; sales of generators and generating sets.