Specialized vehicle manufacturing, sales, technology research and development, technical consultation and after-sales service: Manufacturing and sales of vehicle carriers, on-board chain bodies (excluding pressure vessels), LED electronic display screens; Production, processing and sales of auto parts; Import and export of goods and technologies (excluding those prohibited or restricted by the state and those requiring pre-approval for import and export): Sales of building materials (excluding sand and gravel), hardware and electrical appliances, chemical products (excluding hazardous chemicals and precursor chemicals for drug manufacture), and mineral products. Processing and sales of refrigeration equipment. The above business items do not include those restricted, prohibited by the state or requiring pre-approval.