Sales of mechanical parts and components; Sales of electrical mechanical equipment; Sales of mechanical equipment; Sales of electrical equipment; Sales of metal materials; Sales of instruments; Retail of hardware products; Wholesale of hardware products; Research and development of hardware products; Metal products sales; Metal cutting and welding equipment sales; Sales of electronic special equipment; General equipment repair; Metal cutting machine sales; CNC machine tool sales; Battery sales; Sales of electronic special materials; Import and export of goods; (the project subject to approval according to law shall be approved by the relevant departments before business activities can be carried out)