Honeywell Valve Assembly, 1/2″ FNPT, 2 Way, Modulating/ Floating/ PWM Fail Safe Actuation, 60 Psi Maximum Differential Pressure Rating ( Closeoff ), Selectable 60 or 120 Second Timing, Stem Up to Close A Port, 1.3 Cv, Chilled or Hot Water with up to 60% Glycol