The business scope includes those prohibited by laws, regulations and decisions of the State Council; If the license (examination and approval) is required by laws, regulations and decisions of the State Council, the business shall be operated on the basis of the license (examination and approval) documents after being approved by the examination and approval authority; If the laws, regulations and decisions of the State Council stipulate that there is no need for permission (examination and approval), the market entities shall choose to operate independently. (other comprehensive retail (industry classification); Sales of metal materials and metal products (no centralized trading method shall be adopted for trading, no continuous listing of rights and interests according to standardized trading units, no contract trading in the form of centralized trading, no trading in the form of electronic trading platform, and no business activities in violation of financial regulations); Sales of building materials; Sales of electrical equipment; Sales of electrical and mechanical equipment; Sales of chemical products (excluding licensed chemical products); Instrument sales; Sales of rubber products; Metal structure sales; Import and export of goods and Technology (excluding items restricted and prohibited by the state). (for projects subject to approval according to law, business activities can be carried out only after approval by relevant departments)