Production and sales of plastic films, plastic products, civilian protective masks, protective clothing, non-woven fabrics, and melt-blown fabrics; sales of metal materials, building materials, cables and wires, textiles, knitwear and raw materials, clothing, shoes, and hats, kitchen and sanitary utensils, daily sundries, crafts (excluding cultural relics and ivory products), toys, game products, indoor game equipment, musical instruments, photographic equipment, chemical synthetic materials and chemical raw materials (excluding hazardous chemicals), chemical fibers, synthetic fibers, rubber products, communication equipment (excluding radio transmission devices), electronic machinery, computers and software, equipment, and auxiliary equipment; self-operation and agency import and export business of various commodities and technologies; research, design, sales, and leasing of unmanned aerial vehicles, aviation materials, and aviation parts; biotechnology research and development; research, production, and sales of modified materials.