Gas operation; Construction labor subcontracting; Specialized construction operations; Hazardous waste operation; Production of road motor vehicles; Operation of bonded logistics centers; Construction engineering design; Manufacturing of special equipment; Inspection and testing of special equipment; Design of special equipment; Installation, modification, and repair of special equipment. General items: Manufacturing of metallurgical special equipment; Manufacturing of tunnel construction special machinery; Manufacturing of general equipment (excluding special equipment); Manufacturing of mining machinery; Manufacturing of special equipment for oil drilling; Manufacturing of construction engineering machinery; Manufacturing of mechanical and electrical equipment; Processing of mechanical parts and components; Manufacturing of special machinery for building materials production; Manufacturing of electronic special equipment; Manufacturing of special equipment for oil refining and chemical production; Leasing of mechanical equipment; Mineral processing and selection; Manufacturing of metal processing machinery; Manufacturing of molds; Quenching processing; Sales of molds; Manufacturing of power distribution switchgear equipment; Manufacturing of automotive parts and accessories; Operation of wires and cables; Sales of rail transit engineering machinery and parts; Loading and unloading; Engineering management services; Manufacturing of hydraulic power machinery and components; Sales of power electronic components; Manufacturing of special equipment (excluding licensed special equipment); Manufacturing of metal tools; Metal surface treatment and heat treatment; Manufacturing of gears, gear reducers, and gearboxes; Manufacturing of bearings, gears, and transmission components; Leasing services (excluding licensed leasing services); Leasing of construction engineering machinery and equipment; Manufacturing of wood and bamboo processing machinery; Manufacturing of metal structures; Mineral processing; Manufacturing of metal chains and other metal products; Manufacturing of forgings and powder metallurgy products; Manufacturing of non-ferrous metal alloys; Non-ferrous metal rolling and processing; Casting of non-ferrous metals; Casting of ferrous metals; Spray coating processing; Manufacturing of steam turbines and auxiliary equipment; Manufacturing of water turbines and auxiliary equipment; Manufacturing of metal cutting machine tools; Manufacturing of metal forming machine tools; Manufacturing of casting machinery; Repair of general equipment; Repair of metal products; Repair of special equipment; Manufacturing of machine tool functional components and accessories; Manufacturing of material handling equipment; Manufacturing of hydraulic power machinery and components; Manufacturing of pneumatic power machinery and components; Manufacturing of furnaces, kilns, and electric furnaces; Manufacturing of packaging special equipment; Manufacturing of general parts; Manufacturing of fasteners; Manufacturing of rubber processing special equipment; Manufacturing of environmental protection special equipment; Property management; Daily living services for residents; Manufacturing of agricultural machinery; Manufacturing of electrical machinery special equipment; Manufacturing of domestic waste treatment equipment; Manufacturing of high-speed rail equipment and accessories; Manufacturing of railway locomotive vehicle parts; Processing of non-metal waste and scraps; Foreign contracted projects; Installation services for general mechanical equipment; Earthwork and stonework construction; Land international cargo transportation agency; Electronic weighing services; Domestic cargo transportation agency; General cargo warehousing services (excluding items requiring permits such as hazardous chemicals); Leasing services for transportation equipment; Sales of petroleum products (excluding hazardous chemicals); Sales of metal ores; Sales of forgings and powder metallurgy products; Sales of building materials; Sales of metal materials; Sales of non-metallic ores and products; Sales of construction steel bars; Sales of chemical products (excluding licensed chemical products); Sales of metal products; Manufacturing of cement products; Sales of cement products; Information consulting services (excluding licensed information consulting services); Sales of special equipment; Leasing of special equipment; Metrological technical services; Import and export of goods; Import and export of technology; Import and export agency.