4820-00-974-3928 (25300-4)
NSN 4820-00-974-3928 (NIIN 00-974-3928) is a check valve in Federal Supply Class 4820, Valves, Nonpowered — a valve permitting flow in one direction only. Manufacturer part number 25300-4 (Danfoss Fluid Power IncEasley Opn, CAGE 8Z296); also referenced as 4K13-4S (Danfoss Fluid Power IncEasley Opn).
Key specs: 5000 psi maximum single response operating pressure; full characteristics table below. NIIN assigned January 1962; DEMIL A (none required); unit of issue EA (each), $135.54 gov standard price.