Siemens 171M-10316 2W 1", 63CV BALL VALVE ASSY, CHROME-PLAT BRASS BALL & BRASS STEM, 2-POS, NO, SRSiemens 171M 10316 This 599 Series 2 way ball valve with a 120V, 2 position control, normally open, fail safe actuator assembly, providing 200 psi close off, is used to control hot or chilled water and up to 50% Glycol solution in convectors, fan coil units, unit conditioners, radiation and reheat coils. This 1 inch valve is 63 Cv, full port valve without flow characterizer insert, with chrome plated brass ball and brass stem, and an operating handle