The Valve,safety Relief, cataloged under National Stock Number 4820-01-262-0949, 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 13 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-262-0949 |
| Primary Part Number | 20-CS-169 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Anderson Greenwood Lp Dba Anderson Greenwood Crosby |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Nominal Pipe Size Accommodated | 0.500 INCHES ALL ENDS IN |
| Connection Style | PLAIN,OPTIONAL END(PIPE) ALL ENDS |
| Connection Type | UNTHREADED INTERNAL PIPE ALL ENDS |
| Style Designator | ANGLE |
| Operating Pressure | 440.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Adjustable Pressure Range | +42.0 TO 57.0 POUNDS PER SQUARE INCH LBS |
| Maximum Operating Temp | 150.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Media for Which Designed | WATER, FRESH SINGLE RESPONSE |
| Material | COPPER ALLOY BODY |
| Material | COPPER ALLOY FLOW CONTROL DEVICE |
| 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 |
|---|---|
| 20-CS-169 PRIMARY | Anderson Greenwood Lp Dba Anderson Greenwood Crosby (USA) |
| 20-CS-169-9520 PRIMARY | Anderson Greenwood Lp Dba Anderson Greenwood Crosby (USA) |
| D40HUU-04S-1/2-1/2 PRIMARY | Dante Valve Company (USA) |
| Reference | Meaning |
|---|---|
| D40HUU-04 1/2 IN | 5/9 Secondary reference Danco Valve Company |
| D40HUU-04 1/2 IN | 3/9 Design control — primary reference Dante Valve Company |
NSN 4820-01-262-0949 is a Valve,safety Relief, manufactured by Anderson Greenwood Lp Dba Anderson Greenwood Crosby, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-262-0949 has 3 manufacturer part numbers on file: 20-CS-169 (Anderson Greenwood Lp Dba Anderson Greenwood Crosby), 20-CS-169-9520 (Anderson Greenwood Lp Dba Anderson Greenwood Crosby), D40HUU-04S-1/2-1/2 (Dante Valve Company).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-528-1353. Verify interchangeability with system specifications before substitution.
Key specifications for 20-CS-169: Flow Control Device: DISK; Nominal Pipe Size Accommodated: 0.500 INCHES ALL ENDS IN; Connection Style: PLAIN,OPTIONAL END(PIPE) ALL ENDS; Connection Type: UNTHREADED INTERNAL PIPE ALL ENDS. 13 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.