The Equilibar GSD4SNN4B is a precision dome-loaded back pressure regulator engineered for stable control across gas, liquid, and mixed-phase fluid systems. Utilizing multiple-orifice direct-sealing diaphragm technology, it delivers high turn-down capability and frictionless pressure modulation. Constructed from 316 stainless steel with PTFE and FKM seals, it is rated for working pressures up to 300 psig at temperatures up to 100 °C.