The Caleffi TwistFlow distribution manifolds use integrated balancing valves enabling precise 0.25-gpm to 2-gpm adjustment to each circuit. Distribution manifolds are used for distributing fluid to emitters used in hydronic heating or chilled water systems. Simply twist a circuit stem and read the flow rate on the integral scale. Universal compression fittings are compatible with all brands of PEX or PEX-AL-PEX tubing. TwistTop thermo-electric actuators have “pop-up” indicators that give visual indication that fluid is flowing. The hermetically sealed 6564 Series actuators are effective in accommodating upside-down manifold installations.