Sales of specialized equipment, key systems, and components for rail transit; manufacturing of high-speed rail equipment and accessories; sales of high-speed rail equipment and accessories; intelligent control system integration; manufacturing of electronic specialized equipment; sales of electronic specialized equipment; retail of electronic components; development of rail transit communication and signal systems; manufacturing of railway rolling stock parts; professional design services; industrial engineering design services; technical services, development, consulting, exchange, transfer, and promotion; manufacturing of power transmission and distribution and control equipment; sales of intelligent power transmission and distribution and control equipment; manufacturing of lighting fixtures; sales of lighting fixtures; manufacturing of mechanical and electrical equipment; sales of mechanical and electrical equipment; information consulting services (excluding licensed information consulting services); investment activities using自有 funds; maintenance of railway rolling stock; import and export of goods (excluding goods and technologies restricted or prohibited by the state); (not engaged in financial management, illegal fundraising, illegal deposit absorption, lending, or other businesses; not engaged in securities, futures, trust investment, financial information consulting, or other businesses).