The Valve,safety Relief, cataloged under National Stock Number 4820-00-249-2583, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Dynex/rivett Corp Power Units and Systems. Government technical data includes 7 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-249-2583 |
| Primary Part Number | 8820-01-1-4LP-21 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Dynex/rivett Corp Power Units and Systems |
| Status | ACTIVE |
| Connection Style | PLAIN,OPTIONAL END(PIPE) ALL ENDS |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Operating Pressure | 1000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Thread Series Designator | NPT 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 |
|---|---|
| 8820-01-1-4LP-21 PRIMARY | Dynex/rivett Corp Power Units and Systems (USA) |
| Reference | Meaning |
|---|---|
| 8820-01 1-4LP | 5/9 Secondary reference Dynex/rivett Corp Power Units and Systems |
NSN 4820-00-249-2583 is a Valve,safety Relief, manufactured by Dynex/rivett Corp Power Units and Systems, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-249-2583 has 1 manufacturer part number on file: 8820-01-1-4LP-21 (Dynex/rivett Corp Power Units and Systems).
Key specifications for 8820-01-1-4LP-21: Connection Style: PLAIN,OPTIONAL END(PIPE) ALL ENDS; Connection Type: THREADED INTERNAL PIPE ALL ENDS; Operating Pressure: 1000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS; Thread Direction: RIGHT-HAND ALL ENDS. 7 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.