NIBCO introduces the F739 series of large-diameter manual balancing valves available in sizes 2 1/2” to 16”.  The NIBCO F-739 utilizes a fixed orifice design, and one of the highest rated accuracies in the industry, NIBO says. The F-739 is Class 150 and made of ductile iron. The bolting pattern on the flanges is the same for Class 125 and 150, so regardless of material, they will bolt together. It’s ideal for coils (chilled and hot water), chillers and cooling tower applications in commercial buildings.