Manufacturing of pumps and vacuum equipment; sales of pumps and vacuum equipment; sales of valves and cocks; manufacturing of ordinary valves and cocks (excluding manufacturing of special equipment); sales of pipeline transportation equipment; sales of mechanical equipment; installation services of general mechanical equipment; manufacturing of special equipment (excluding manufacturing of licensed professional equipment) ); maintenance of electronic and mechanical equipment (excluding special equipment); sales of electronic products; technical services, technology development, technical consultation, technology exchange, technology transfer, technology promotion; sales of metal products; sales of electrical equipment; retail of hardware products; wholesale of hardware products; manufacturing of hardware products; Manufacturing of capacitors and their supporting equipment; sales of capacitors and their supporting equipment; manufacturing of metal materials; sales of metal materials; sales of building materials; processing of construction stones; manufacturing of lightweight building materials; sales of lightweight building materials; repair of instruments; manufacturing of instruments; sales of instruments; wholesale of auto parts; retail of auto parts; manufacturing of auto parts and accessories; manufacturing of motorcycle parts; wholesale of motorcycles and parts; retail of motorcycles and parts; production of chemical products (excluding licensed chemical products); sales of chemical products (excluding licensed chemical products).