The Zurn 34-70XLDU 3/4" double union FNPT water pressure reducing valve Ideal for use where Lead-Free* valves are required. Designed for installation on potable water lines to reduce high inlet pressure to a lower outlet pressure. The unitized replaceable cartridge reduces time involved with cleaning and maintenance. The direct acting integral bypass design prevents buildup of excessive system pressure caused by thermal expansion. The balanced piston design enables the regulator to react in a smooth and responsive manner to changes in system flow demand, while at the same time, providing protection from inlet pressure changes.