Manufacturing of railway rolling stock; design of railway rolling stock; maintenance of railway rolling stock; design of special equipment; manufacturing of special equipment; inspection and testing of special equipment; installation, modification, and repair of special equipment; electrical installation services. General items: Sales of railway rolling stock; manufacturing of urban rail transit equipment; manufacturing of narrow-gauge rolling stock; sales of special equipment; manufacturing and sales of railway rolling stock parts; manufacturing and sales of high-speed rail equipment and parts; sales of specialized rail transit equipment, key systems, and components; sales of complete new energy vehicles; research and development of metal products; sales and repair of metal products; manufacturing and sales of cork products; manufacturing of general equipment (excluding special equipment); sales of mechanical equipment; sales of railway-specific measuring or inspection instruments; sales and repair of electrical equipment; installation services for general mechanical equipment; repair of general equipment; maintenance of electronic and mechanical equipment (excluding special equipment); manufacturing of cloud computing equipment; manufacturing and sales of IoT equipment; IoT technical services; manufacturing, sales, and repair of instruments; software development and sales; internet security services; security system monitoring services; design and construction services for security technology prevention systems; digital technology services; system integration services; system operation and maintenance services; geographic remote sensing information services; development of artificial intelligence applications; sales of artificial intelligence hardware; system integration services for artificial intelligence industries; software outsourcing services; certification consulting; business training (excluding educational and vocational training requiring licenses); technical services, development, consulting, exchange, transfer, and promotion; import and export of goods and technologies; leasing of non-residential real estate.