Plast-O-Matic Valves, Inc. has introduced a new automatic valve that performs multiple functions in a piping system, including pressure relief, backpressure control, pump bypass and anti-siphon protection. The new, ½” size, lug-mounted Series RVDT uses an adjustable non-wetted spring to control backpressure in a piping system. The set-point is adjustable, and once the set pressure is reached, the valve begins to open. It will allow the rated full flow at approximately 40 percent over the set pressure. This operation enables the valve to provide a controlled obstruction in a piping system as needed. This is invaluable in providing backpressure on a pump, or backpressure to maintain flow to points of use.