Type 6518 is a pilot-operated 3/2-way valve, and type 6519 is a 5/2 or 5/3-way valve. Together, they form a series. The valves can be used individually or in blocks. They operate without continuous air consumption and are designed to control double-acting or single-acting actuators. A solenoid valve of type 6014 serves as the pilot control. The use of high-quality materials allows the valves to be used in outdoor and chemical environments. The series includes devices with Ex approval and NAMUR flange design. With the valve operating modes C, D, and H monostable, a safety level of SIL2 can be achieved according to IEC 61508, depending on the architecture of the safety device.