Manufacturing of special-purpose vehicles and trailers (specific products subject to announcements by the Ministry of Industry and Information Technology); Development, manufacturing, sales, and related technical services of vehicle bodies and parts for automobiles and engineering machinery vehicles; Modification, sales, and technical services of special-purpose vehicles (specific products subject to announcements by the Ministry of Industry and Information Technology); Motor vehicle repair; Manufacturing, sales, and leasing of engineering machinery; Sales of automobiles (excluding passenger cars), metal materials, metal products, hardware products, and chemical products (excluding Class I precursor chemicals and hazardous chemicals); Leasing of self-owned houses and sites; Research, development, design, sales, after-sales service, and parts manufacturing of new energy vehicles; General road freight transport; Manufacturing, processing, and installation of metal structural parts; Design and construction of steel structures; Import or export of goods and technology (excluding goods and technology prohibited by the state or subject to administrative approval).