The Valve,safety Relief, cataloged under National Stock Number 4820-00-166-9404, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 13 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-166-9404 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | STEM |
| Connection Style | PLAIN (TUBE) FIRST END |
| Connection Style | BARBED-BEADED (HOSE) SECOND END |
| Nominal Inside Diameter Hose Accommodated | 0.250 INCHES SECOND END IN |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | UNTHREADED EXTERNAL HOSE SECOND END |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF SEPARABLE SECTIONS. |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.250 INCHES FIRST END IN |
| Thread Class | 2A FIRST END A |
| Material | ALUMINUM ALLOY OVERALL |
| Thread Series Designator | UNEF 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 |
| Reference | Meaning |
|---|---|
| 75704-21 | 3/2 Design control — primary reference U.S. Government activity |
| 75704-21 | 5/9 Secondary reference Trico Products Corporation |
NSN 4820-00-166-9404 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-166-9404: Flow Control Device: STEM; Connection Style: PLAIN (TUBE) FIRST END; Connection Style: BARBED-BEADED (HOSE) SECOND END; Nominal Inside Diameter Hose Accommodated: 0.250 INCHES SECOND END IN. 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.