The Valve,safety Relief, cataloged under National Stock Number 4820-01-280-2983, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Anderson Greenwood Lp Dba Anderson Greenwood Crosby. Government technical data includes 15 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-01-280-2983 |
| Primary Part Number | 1/2 FIGURE 80-4S 20IN HG |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Anderson Greenwood Lp Dba Anderson Greenwood Crosby |
| Status | ACTIVE |
| Flow Control Device | BALL |
| Connection Style | PLAIN,OPTIONAL END(PIPE) SECOND END |
| Connection Style | PLAIN (PIPE) FIRST END |
| Connection Type | THREADED INTERNAL PIPE SECOND END |
| Connection Type | THREADED EXTERNAL PIPE FIRST END |
| Style Designator | ANGLE |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.750 INCHES SECOND END IN |
| Nominal Thread Size | 0.500 INCHES FIRST END IN |
| Material | COPPER ALLOY BODY |
| Material | STEEL CORROSION RESISTING FLOW CONTROL DEVICE |
| Material | STEEL CORROSION RESISTING SEAT |
| Thread Series Designator | NPT SECOND END |
| Thread Series Designator | NPT FIRST END |
| 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 |
|---|---|
| 2503156 | Evac North America Inc (USA) |
| 1/2 FIGURE 80-4S 20IN HG PRIMARY | Anderson Greenwood Lp Dba Anderson Greenwood Crosby (USA) |
| C10977 | Anderson Greenwood Lp Dba Anderson Greenwood Crosby (USA) |
| Reference | Meaning |
|---|---|
| 2503156 | 5/9 Secondary reference Envirovac Inc Dba Monogram Systems-Rockford Div |
NSN 4820-01-280-2983 is a Valve,safety Relief, manufactured by Anderson Greenwood Lp Dba Anderson Greenwood Crosby, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-280-2983 has 3 manufacturer part numbers on file: 2503156 (Evac North America Inc), 1/2 FIGURE 80-4S 20IN HG (Anderson Greenwood Lp Dba Anderson Greenwood Crosby), C10977 (Anderson Greenwood Lp Dba Anderson Greenwood Crosby).
Key specifications for 1/2 FIGURE 80-4S 20IN HG: Flow Control Device: BALL; Connection Style: PLAIN,OPTIONAL END(PIPE) SECOND END; Connection Style: PLAIN (PIPE) FIRST END; Connection Type: THREADED INTERNAL PIPE SECOND END. 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.