A manifold is a device in a water system used for connecting supply and return water to various heating pipes. The material for manifolds used in underfloor heating and air conditioning systems should be brass, while those for household meter replacement in potable water supply systems are typically made of PP or PE. Both supply and return lines should have air release valves, and many manifolds also feature drain valves. A "Y" type filter should be installed at the water supply inlet. Each branch of the water supply pipe should be equipped with a valve to adjust the water flow.