Production, sales, installation, and maintenance of doors, door curtains, and metal doors and windows (not produced here); technology development, technical consultation, technology transfer, and technical services for automated doors and windows; wholesale of building materials, mechanical equipment and accessories, plastic products, metal materials, insulation materials, Wujinjiaodian, electronic products and accessories, industrial automation equipment, rubber products, rock wool products, glass wool products, office supplies, chemical products (excluding hazardous chemicals), auto parts, motorcycle accessories, and fabric products.