Energy-saving and environmental protection technology development and services; cable tray manufacturing; building air conditioning equipment、 Ventilation equipment system installation services, electrical equipment wholesale, Internet of Things technology research and development, mechanical technology promotion services, power electronics technology services, environmental technology development services, and environmental technology consulting.、 Communication services, IoT device sales, construction engineering、 Civil engineering technical services, intelligent machine system technical services, electromechanical equipment installation services, electromechanical equipment installation engineering professional contracting, building materials、 Wholesale decorative materials, steel structure manufacturing, building steel structure、Precast component installation services, building construction services, landscaping services, ancient building services, new material technology promotion services, overseas contracting services, monitoring system installation services, electronic automation installation services, electronic equipment installation services, intelligent installation services, building equipment automatic control system services, security monitoring and burglar alarm system services, smart card system services, communication system services, fire protection facilities engineering professional contracting, energy-saving technology promotion services, elevator installation services, post-construction decoration services.、 Decoration and earthwork clearing services, project management services, EPC (Engineering, Procurement, and Construction) services, EPC cost consulting services, engineering survey and design, mechanical engineering design services, electronic engineering design services, environmental technology promotion services, and Internet of Things (IoT) services.( Except telecommunications companies)