General items: Manufacturing of metal chains and other metal products; Sales of metal chains and other metal products; Metal material manufacturing; Sales of metal materials; Non-ferrous metal alloy manufacturing; Non-ferrous metal alloy sales; Metal structure manufacturing; Metal structure sales; Sales of metal products; Steel rolling; Sales of construction reinforcement products; Manufacturing and processing of doors and windows; Door and window sales; Wholesale of hardware products; Sales of high-performance nonferrous metals and alloy materials; Non-ferrous metal calendering. (In addition to the items that need to be approved according to law, the business activities shall be carried out independently according to law with the business license) Licensed items: Import and export of goods. (Projects that need to be approved according to law can only be operated with the approval of relevant departments. The specific operation items shall be subject to the approval documents or licenses of relevant departments)