Technical services, technical development, technical consulting, technical exchange, technology transfer, and technology promotion; professional design services; industrial design services; wind power generation technical services; solar power generation technical services; metal surface treatment and heat treatment processing; manufacturing of fasteners; sales of fasteners; manufacturing of metal structures; sales of metal structures; sales of wind turbine generator sets and parts; manufacturing of power electronic components; sales of power electronic components; manufacturing of power facility equipment; sales of power facility equipment; manufacturing of railway locomotive and rolling stock parts; sales of railway locomotive and rolling stock parts; manufacturing of photovoltaic equipment and components; sales of photovoltaic equipment and components; leasing of photovoltaic power generation equipment; manufacturing of metal products for safety and fire protection; manufacturing of metal products for building decoration, water heating pipes, and other building uses; manufacturing of metal chains and other metal products; sales of metal products; manufacturing of automotive parts and accessories; wholesale of automotive parts; retail of automotive parts; manufacturing of metal signs for traffic and public management; sales of signs for traffic and public management; manufacturing of plastic products; sales of plastic products; sales of rubber products; sales of glass fiber reinforced plastic products; manufacturing of pneumatic and electric tools; sales of pneumatic and electric tools; manufacturing of metal tools; sales of metal tools; manufacturing of hardware products; wholesale of hardware products; retail of hardware products; sales of labor protection supplies; sales of timber; sales of fire protection equipment; import and export of goods. Permitted items: construction labor subcontracting; construction engineering construction.