4820-01-406-8829 (2021400241M)
NSN 4820-01-406-8829 (NIIN 01-406-8829) is a safety relief valve in Federal Supply Class 4820, Valves, Nonpowered — a valve designed to automatically release excessive pressures. Manufacturer part number 2021400241M (Emerson Automation Solutions Final, CAGE 15187); also referenced as 20214, 2021400241M 4.0 (Anderson Greenwood Lp).
Key specs: 150 psi maximum single response operating pressure; full characteristics table below. NIIN assigned January 1995; DEMIL A (none required); unit of issue EA (each), $32,829.20 gov standard price; export Schedule B 8481.40.0000.