Series 3 solenoid valves with G1/8 and G1/4 ports have been designed in the 3/2, 2 x 3/2, 5/2, 5/3 versions and with the following two devices of actuation: - Electropneumatically actuated with mechanical spring return - Electropneumatically actuated with external and internal air pressure supply Series 3 valves are equipped with a manual override which allows a stable operation and they can use Series U or G solenoids (22x22). Pneumatically actuated valves 3/2 NC become NO when the supply is on connection 3.