Traditional valve manifolds are constructed with glued PVC or threaded Schedule 80 risers and are very difficult to service. The heavy-duty pre-assembled valve manifold is a fully engineered and assembled single or multi-zone valve system which provides optimum serviceability. The pre-assembled manifold has special swivel unions which create a secure, watertight seal against each manifold component and the valves. If you ever need to add a valve or replace a valve, the procedure is as simple as unthreading the swivel, sliding it back, and adding or replacing the valve. The process of adding a drip filter and pressure regulator is equally simple. The valves are premium L-Series valves with internal-bleed, 24 VAC solenoids which are compatible with controllers from Orbit, Hydro-Rain, and other major brands. A wide variety of additional manifold fittings can be purchased separately. For a professional-quality manifold installation, mount the preassembled manifold on the valve box base with a standard valve box covering it. For outdoor irrigation use with cold water only.