Guage ValveGuage Valve Features: Body material in Stainless Steel 316 or 304. Max.working pressure to 6000 psig (413 bar) at 37°C. TFM1600 packing as standard; Graphite packing for option. Lagging extension body available for insulation clearance. 1/2" or 3/4" male NPT inlet port and 1/2" female NPT outlet port configuration. 1/2" female NPT gauge port standard. 100% factory tested. Product Name: Gauge Valve - NV33P. Gauge Valve - GRV-S. Gauge Valve - GRV-L. Gauge Valve - GRV2.