Sale of PP Plastic pellet chemical product (excluding hazardous chemicals) and raw materials, mechanical and electrical equipment, piping equipment, refrigeration equipment, heating equipment, computer software and hardware, electronic products, construction materials, metallic materials (excluding rare and other restricted metals) and decorative materials; Technical development and maintenance of electronic products; Computer software and hardware development; Business information consulting; Enterprise management consulting; Website development and technical maintenance; Network system technical maintenance; Computer network technical consultation; Domestic trade; Educational information consultation; Education and training; Computer system integration; House leasing (the above items do not include the items prohibited by laws, administrative regulations and decisions of The State Council and subject to prior approval, and the restricted items shall be operated only after obtaining permission)