Technical Specifications Category Specification Type Direct-Acting, Spring-Loaded Pressure Relief Valve Service Gas, Liquid, and Steam (dependent on model and trim) Set Pressure Range CSB400 (Standard Spring): 20 to 450 psig (1.4 to 31 bar) CSB400L (Low-Pressure Spring): 5 to 200 psig (0.3 to 14 bar) Temperature Range Standard: -20° to 300°F (-29° to 149°C) High-Temp Soft Seat: Up to 400°F (204°C) End Connections 1/2 in., 3/4 in., 1 in. NPT (National Pipe Thread) 1/2 in., 3/4 in., 1 in. SW (Socket Weld) Body Materials Carbon Steel (Standard), 316 Stainless Steel, Bronze Trim Materials 316 Stainless Steel (standard stem & guide), Nitrile (standard seat) Soft Seat Materials Nitrile (Buna-N), Fluorocarbon (Viton), Ethylene Propylene (EPDM), Perfluoroelastomer (FFKM) Flow Characteristic Snap-acting (pop) action for gas/vapor; modulating action for liquid.