The Valve,check, cataloged under National Stock Number 4820-01-351-9891, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Naval Sea Systems Command. Government technical data includes 14 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-351-9891 |
| Primary Part Number | 6369123-3 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | GASKET SEAL (BOSS) ALL ENDS |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED INTERNAL BOSS ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 125.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.750 INCHES ALL ENDS IN |
| Maximum Operating Temp | 185.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Media for Which Designed | WATER, FRESH SINGLE RESPONSE |
| Thread Class | 3B ALL ENDS |
| Material | STEEL BODY |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) ALL ENDS |
| Valve Operation Method | AUTOMATIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 6369123-3 PRIMARY | Naval Sea Systems Command (USA) |
| Reference | Meaning |
|---|---|
| 0666-05-6.0 | 5/2 Secondary reference U.S. Government activity |
| 6369123 | 7/1 Vendor item drawing reference Naval Sea Systems Command |
NSN 4820-01-351-9891 is a Valve,check, manufactured by Naval Sea Systems Command, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-351-9891 has 1 manufacturer part number on file: 6369123-3 (Naval Sea Systems Command).
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-351-9893, 4820-01-352-2258. Verify interchangeability with system specifications before substitution.
Key specifications for 6369123-3: Flow Control Device: DISK; Connection Style: GASKET SEAL (BOSS) ALL ENDS; Mounting Position: HORIZONTAL OR VERTICAL; Connection Type: THREADED INTERNAL BOSS ALL ENDS. 14 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.