4820-01-472-5101 (5231-B)
NSN 4820-01-472-5101 (NIIN 01-472-5101) is a safety relief valve in Federal Supply Class 4820, Valves, Nonpowered — a valve designed to automatically release excessive pressures. Manufacturer part number 5231-B; also referenced as 5231-B 300PSI (Henry Technologies, Inc.).
Key specs: 300 psi maximum single response operating pressure; full characteristics table below. NIIN assigned March 2000; DEMIL A (none required); ESD/EMI-sensitive; export Schedule B 8481.40.0000.