The Caleffi 6646B12 is a genuine pre-assembled distribution manifold specifically designed for underfloor radiant heating systems. This high-quality brass manifold features 2 groups, each equipped with adjustable flow meters for precise control, ranging from 0.5 to 5 liters per minute. It includes 1" female main connections and 3/4" Eurocone branch connections, ensuring compatibility with standard heating components. Built to withstand a maximum working pressure of 6 bar and a maximum working temperature of 90 °C, it provides reliable and efficient performance. The unit comes complete with supply and return manifolds, shut-off valves, and sturdy metal brackets for straightforward installation. Ideal for controlled and effective heat distribution in residential and commercial underfloor heating applications.