The PR3& PR4 from Omnidea-RTG is a Spacecraft Valve with Mass 0.726 kg, Operating Pressure 310 bar, Regulated Pressure 1 bar, 2 bar, 3.5 bar, External Leakage Time 0.1 scc/h, Internal Leakage Time 0.1 scc/h. More details for PR3& PR4 can be seen below.
