The Valve,safety Relief, cataloged under National Stock Number 4820-00-201-8499, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Market Forge Industries Inc. Government technical data includes 16 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-201-8499 |
| Primary Part Number | 10-4741 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Market Forge Industries Inc |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | PLAIN,OPTIONAL END(PIPE) FIRST END |
| Connection Style | PLAIN (PIPE) SECOND END |
| Connection Type | THREADED INTERNAL PIPE FIRST END |
| Connection Type | THREADED EXTERNAL PIPE SECOND END |
| Style Designator | ANGLE |
| Operating Pressure | 800.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.750 INCHES SECOND END IN |
| Nominal Thread Size | 0.750 INCHES FIRST END IN |
| Material | COPPER ALLOY OVERALL |
| Thread Series Designator | NPT SECOND END |
| Thread Series Designator | NPT FIRST END |
| Valve Discharge Flow Rate | 266.0 POUNDS PER HOUR LBS |
| Valve Operation Method | AUTOMATIC OR MANUAL |
| 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 |
|---|---|
| 10-4741 PRIMARY | Market Forge Industries Inc (USA) |
| Reference | Meaning |
|---|---|
| 15 3-4-8 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-00-201-8499 is a Valve,safety Relief, manufactured by Market Forge Industries Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-201-8499 has 1 manufacturer part number on file: 10-4741 (Market Forge Industries Inc).
2 possible matches (shared part number, not a government interchangeability claim): 4320-01-194-2696, 4730-01-555-5620. Verify interchangeability with system specifications before substitution.
Key specifications for 10-4741: Flow Control Device: POPPET; Connection Style: PLAIN,OPTIONAL END(PIPE) FIRST END; Connection Style: PLAIN (PIPE) SECOND END; Connection Type: THREADED INTERNAL PIPE FIRST END. 16 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.