Bed sales; Mold sales; Sales of pumps and vacuum equipment; Sales of environmental emergency technical equipment; Sales of environmental emergency testing instruments and meters; Sales of mechanical parts and components; Sales of specialized environmental protection equipment; Sales of pneumatic power machinery and components; Sales of gas compression machinery; Sales of specialized teaching instruments; Sales of photocopying and offset printing equipment; Sales of electric dynamometer motors; Sales of electrical instruments and meters; Sales of electrical equipment; Sales of electronic products; Sales of calculator equipment; Sales of testing machines; Sales of navigation, surveying, meteorological, and marine specialized instruments; Rental services (excluding publication rental); Conference and exhibition services; Sales of specialized environmental monitoring instruments and meters; Special equipment repair; Environmental consulting services; Electrical equipment repair; Sales of electrical equipment; Sales of ovens, furnaces, and electric furnaces; Software development; Sales of metal materials; Sales of electrical signal equipment and devices; Repair of instruments and meters; Sales of intelligent instruments and meters; Sales of electronic measuring instruments; Retail of electronic components; Sales of electronic specialized equipment; Wholesale of hardware products; Wholesale of computer software, hardware, and auxiliary equipment; Retail of computer software, hardware, and auxiliary equipment; Sales of office supplies; Wholesale of sports goods and equipment; Retail of sports goods and equipment; Needle textiles