The Seat,valve, cataloged under National Stock Number 4820-00-504-8129, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 12 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-504-8129 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.100 INCHES NOMINAL IN |
| Flange Diameter | 0.750 INCHES NOMINAL IN |
| Thread Length | 0.306 INCHES NOMINAL SINGLE THREADED PORTION IN |
| Style Designator | THREADED FLANGED |
| Body Inside Diameter | 0.325 INCHES NOMINAL IN |
| Nominal Thread Size | 0.625 INCHES SINGLE THREADED PORTION IN |
| Surface Treatment | CHROMATE OVERALL |
| Under Flange Height | 0.312 INCHES NOMINAL IN |
| Thread Class | 2A SINGLE THREADED PORTION A |
| Material | STEEL OVERALL |
| Thread Series Designator | UNEF SINGLE THREADED PORTION |
| Seating Surface Shape | FLAT |
| 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 |
|---|---|
| 26YD-801X2PC1 | 5/9 Secondary reference U.S. Government activity |
| 72791-21X03 | D/9 Drawing number reference only U.S. Government activity |
| 72791-21X3PC17 | 3/2 Design control — primary reference U.S. Government activity |
| 516-4391370 | D/9 Drawing number reference only Naval Sea Systems Command |
NSN 4820-00-504-8129 is a Seat,valve, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-504-8129: Flange Seat to Disk End Height: 0.100 INCHES NOMINAL IN; Flange Diameter: 0.750 INCHES NOMINAL IN; Thread Length: 0.306 INCHES NOMINAL SINGLE THREADED PORTION IN; Style Designator: THREADED FLANGED. 12 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.