High-voltage testing equipment, high-voltage measuring instruments, electrical automation equipment, switching power supplies, box-type transformers, intelligent switchgear development, production, and sales; Sales of hardware, electrical appliances, mechanical and electrical equipment and accessories, agricultural machinery and accessories, wires and cables, power engineering testing vehicles, aerial work vehicles, and auto parts; Power engineering design, installation, maintenance, and repair services. General projects: Plastic product manufacturing; Special chemical product sales (excluding hazardous chemicals); Pipeline transportation equipment sales; Pump and vacuum equipment manufacturing; Pump and vacuum equipment sales; Glass fiber reinforced plastic product manufacturing; Glass fiber reinforced plastic product sales; Photovoltaic equipment and component manufacturing; Photovoltaic equipment and component sales; Metal structure manufacturing; Metal structure sales; Environmental monitoring special instrument manufacturing; Environmental monitoring special instrument sales; Dust removal technology equipment manufacturing; Environmental protection special equipment manufacturing; Ferrous metal casting; Steel rolling processing; Land pipeline transportation; Anti-corrosion material sales; Technical services, technical development, technical consulting, technical exchange, technology transfer, and technology promotion; Earthwork engineering construction; Plastic product sales; Building decoration, water and heating pipeline parts, and other building metal product manufacturing.