Air purification equipment research and development, production and sales; Water treatment equipment, mechanical and electrical equipment, electronic products, hardware accessories, protective supplies sales; Provide technical service and after-sale service for related products; Mechanical and electrical equipment installation engineering, HVAC engineering, clean room engineering, pipeline engineering, indoor and outdoor decoration engineering, environmental protection engineering; Engaged in import and export business of goods and technology. Production of labor protection articles; Sales of labor protection articles; Daily use of masks (non-medical) sales; Production of daily masks (non-medical); Production of special labor protection articles; (For projects subject to approval according to law, business activities can only be carried out after approval by relevant departments)