The selector switch is for the expansion unit. 6AV7674-1MD00-0AA0Siemens man-machine interface

Sales of industrial automatic control system devices; General machinery and equipment installation services, import and export of goods; Technology import and export; Import and export agent, communication equipment repair; Maintenance of electronic and mechanical equipment (excluding special equipment); Sales of CNC machine tools; Wire and cable business; Wholesale of hardware products; Retail of hardware products; Instrument sales; Electrical equipment repair; Sales of electrical equipment; Sales of mechanical and electrical equipment; Sales of machinery and equipment; Sales of mechanical parts and components; Sales of electronic components and electromechanical components; Sales of special electronic equipment; Sales of electronic products; Wholesale of electronic components; Retail of electronic components; Technical service, technical development, technical consultation, technical exchange, technology transfer and technology promotion. (Except for projects that need to be approved according to law, business activities shall be carried out independently according to law with the business license)