Siemens 599-01081 VALVE ACTUATOR, PNEUMATIC, 4-INCH, 3 TO 8 PSI, 3/4 INCH STROKE, 1/8-INCH NPTSiemens 599 01081 Valve Actuator, Pneumatic, 4 inch, 3 to 8 psi, 3 4 inch Stroke, 1 8 inch NPT This Flowrite 599 Series 4 inch Pneumatic Valve Actuator is designed for use with Flowrite 599 Series valves in liquid and steam service applications. This valve actuator has a 3 4 inch stroke, a nominal spring range of 3 to 8 psi, a max diaphragm pressure of 35 psi (241 kPa), and a 1 8 inch NPT air connection. Other features of this valve actuator include