Sales of wires and cables; sales of metal structures; manufacturing of metal structures; sales of electrical accessories; sales of mechanical and electrical equipment; sales of power distribution switchgear equipment; manufacturing of power distribution switchgear equipment; retail of electronic components; manufacturing of mechanical and electrical equipment; sales of railway locomotives and rolling stock; sales of railway locomotive and rolling stock parts; sales of construction machinery; sales of electronic special equipment; sales of instruments and meters; manufacturing of electrical instruments and meters; sales of molds; manufacturing of molds; manufacturing of urban rail transit equipment; manufacturing of environmental protection special equipment; sales of environmental protection special equipment; manufacturing of environmental monitoring special instruments; repair of electrical equipment; research and development of IoT technology; IoT technical services; IoT application services; sales of IoT equipment; sales of information security equipment; sales of lighting fixtures; research and development of power distribution switchgear control equipment; manufacturing of optical cables; sales of optical cables; sales of valves and cocks; research and development of valves and cocks; sales of gas compression machinery; manufacturing of gas compression machinery; manufacturing of testing machines; sales of testing machines; sales of Class I medical devices; sales of Class II medical devices; video production services; digital content production services (excluding publication and distribution); industrial internet data services; digital technology services; internet data services; sales of electronic products; sales agency. Licensed items: manufacturing of wires and cables; construction engineering design; maintenance of railway locomotives and rolling stock; operation of online cultural activities; live streaming technical services; internet information services.