4820-01-211-0939 (20154G11M)
NSN 4820-01-211-0939 (NIIN 01-211-0939) is a safety relief valve in Federal Supply Class 4820, Valves, Nonpowered — a valve designed to automatically release excessive pressures. Manufacturer part number 20154G11M (Emerson Automation Solutions Final, CAGE 15187); also referenced as 20154 (Anderson Greenwood Lp).
Key specs: 3450 psi maximum single response operating pressure; full characteristics table below. NIIN assigned June 1985; DEMIL A (none required); unit of issue EA (each), $1,418.83 gov standard price; export Schedule B 8481.40.0000.