SK Flow regulator valve, 3/4x3/4" volumetric flow control, for Air/water heat exchanger, Flow regulator valve, Brass, 84818073, 1 pc(s), 0.375 lbs, 4028177448667, For use with air/water heat exchangers, especially if more than one heat exchanger (n > 1) is used in the water cooling circuit. The correctly set valve ensures the same quantity of cooling medium for all equipment.