Siemens 371-03018 VALVE ASSY 2W NC 1/2", 1CV, LIN, SS TRIM FXF, PROP ELECTRONIC ACT NSRSiemens 371 03018 Valve assy 2W NC 1 2", 1Cv, Lin, SS Trim FxF, Prop Electronic Act NSR Flowrite 599 Series Valve Assembly features a proportional control (0 to 10 Vdc or 4 to 20 mA), non spring return, 24 Vac electronic actuator. The 2 way, normally closed, 1 2 inch, 1 Cv valve assembly is ANSI Class 250 and has a linear characteristic, stainless steel trim, and female x female end connections. Additional Information Valve TypeTwo way Valve Body