The Valve,check, cataloged under National Stock Number 4820-01-354-8938, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Meggitt Defense Systems, Inc. Dba Meggitt Defense Systems Inc. Government technical data includes 15 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through both NSN and commercial part number lookups. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-354-8938 |
| Primary Part Number | 333591P01 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Meggitt Defense Systems, Inc. Dba Meggitt Defense Systems Inc |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | EXTERNAL SEAT FOR GASKET SEAL (BOSS) ALL ENDS |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED EXTERNAL BOSS ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 3000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Seat Angle | 37.0 DEGREES ALL ENDS |
| Maximum Operating Temp | 300.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE |
| Media for Which Designed | WATER-OIL-GAS SINGLE RESPONSE |
| Material | ALUMINUM BODY |
| Thread Series Designator | UN ALL ENDS |
| Opening Pressure Setting | 2.0 POUNDS PER SQUARE INCH LBS |
| 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 |
|---|---|
| 333591P01 | Meggitt Defense Systems, Inc. Dba Meggitt Defense Systems Inc (USA) |
| Reference | Meaning |
|---|---|
| 333591P01 | 5/9 Secondary reference Meggitt Defense Systems, Inc. Dba Meggitt Western Design |
| 1310A-18 | 3/2 Design control — primary reference U.S. Government activity |
| 1310A-18-2 | 5/9 Secondary reference U.S. Government activity |
| 333591 | 5/9 Secondary reference Howden Fluid Systems |
| 333591P01 | 5/9 Secondary reference Howden Fluid Systems |
NSN 4820-01-354-8938 is a Valve,check, manufactured by Meggitt Defense Systems, Inc. Dba Meggitt Defense Systems Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-354-8938 has 1 manufacturer part number on file: 333591P01 (Meggitt Defense Systems, Inc. Dba Meggitt Defense Systems Inc).
Key specifications for 333591P01: Flow Control Device: DISK; Connection Style: EXTERNAL SEAT FOR GASKET SEAL (BOSS) ALL ENDS; Mounting Position: HORIZONTAL OR VERTICAL; Connection Type: THREADED EXTERNAL BOSS ALL ENDS. 15 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.