The Valve,safety Relief, cataloged under National Stock Number 4820-01-644-6963, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 4 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-644-6963 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Mounting Facility | THREADED FASTENER |
| Thread Series Designator | NPTF SECOND END |
| Thread Series Designator | NPT FIRST END |
| 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 |
|---|---|
| 977659-01 | 3/9 Design control — primary reference Control Flow, Inc. Dba Westech Heavy Machinery Division Div Westech Heavy Machinery Division |
NSN 4820-01-644-6963 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-644-6963: Nominal Thread Size: 0.250 INCHES ALL ENDS IN; Mounting Facility: THREADED FASTENER; Part Name Assigned by Controlling Agency: VALVE,RELIEF,1/4 MNPT X 1/4 FNPT; End Item Identification: SHOCK ABSORBER. 4 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.