The Stem,fluid Valve, cataloged under National Stock Number 4820-01-508-4426, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 5 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-508-4426 |
| Item Name | Stem,fluid Valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Valve Type for Which Designed | RELIEF |
| Stem Actuating End Type | THREADED INTERNALLY |
| Material Document and Classification | QQ-S-763 FED SPEC SINGLE MATERIAL RESPONSE OR ASTM A581 OR A582 ASSN STD SINGLE MATERIAL RESPONSE OR AMS 5640 ASSN STD SINGLE MATERIAL RESPONSE |
| Valve Size for Which Designed | 1.000 INCHES IN |
| Material | STEEL CORROSION RESISTING |
| 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 |
|---|---|
| 185795-0030 | 3/2 Design control — primary reference U.S. Government activity |
| 284799-0001 ITEM 21 | 5/2 Secondary reference U.S. Government activity |
| P185795-0030 | 5/2 Secondary reference U.S. Government activity |
| 284799-0001 | D/9 Drawing number reference only U.S. Government activity |
NSN 4820-01-508-4426 is a Stem,fluid Valve, classified under FSC 4820, Valves, Nonpowered. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-508-4711, 4820-01-508-4718. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-01-508-4426: Valve Type for Which Designed: RELIEF; Stem Actuating End Type: THREADED INTERNALLY; Material Document and Classification: QQ-S-763 FED SPEC SINGLE MATERIAL RESPONSE OR ASTM A581 OR A582 ASSN STD SINGLE MATERIAL RESPONSE OR AMS 5640 ASSN STD SINGLE MATERIAL RESPONSE; Valve Size for Which Designed: 1.000 INCHES IN. 5 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.