ASCO series 520 subbases are available with bottom or side ports and can be connected to the control panel through various types of fittings, such as conduit fittings, plug-in fittings or cable glands. The electrical and pneumatic connections are made with high-quality components and are designed to ensure a reliable and efficient performance. The set includes manual spool position testers and can be fitted with a variety of solenoid valves and air operated valves to meet specific requirements. The series 520 solenoid air operated distribution set provides a compact and cost-effective solution for controlling the flow of air in pneumatic systems.