Research, development, manufacturing, and sales of explosion-proof electrical appliances, explosion-proof lighting fixtures, explosion-proof pipe fittings, explosion-proof components, explosion-proof instruments, explosion-proof accessories, explosion-proof positive pressure cabinets, explosion-proof motors, explosion-proof fans, explosion-proof handheld terminal devices, explosion-proof transformers, explosion-proof alloy tools, and power distribution switch control equipment; Research, development, production, sales, installation, and maintenance of explosion-proof refrigerators, explosion-proof air conditioners, explosion-proof dehumidifiers, explosion-proof humidifiers, molds, communication equipment, lighting fixtures, distribution boxes, marine supporting equipment, electronic components, plastic parts, and low-voltage electrical appliances and accessories; Sales of explosion-proof cables; Electrical maintenance; Road lighting engineering construction; Technical development, technology transfer, technical consultation, and technical services in the field of explosion-proof, electrical, and appliance technology; Import and export business of goods and technology (excluding goods and technology prohibited or restricted by the state).