The Seat,valve, cataloged under National Stock Number 4820-01-439-1891, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-439-1891 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| 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 |
|---|---|
| 17720233A 100M ITEM 2 | 5/9 Secondary reference Seffle Marine Ltd |
| 17720233 100MM ITEM 2 | 5/9 Secondary reference Halla Hydro Ab |
| 17720233 | D/9 Drawing number reference only Halla Hydro Ab |
| 17720233A 100MM AH ITEM 2 | 3/9 Design control — primary reference Halla Hydro Ab |
NSN 4820-01-439-1891 is a Seat,valve, classified under FSC 4820, Valves, Nonpowered. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-439-1892, 4820-01-439-1893. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-01-439-1891: End Item Identification: STRATEGIC SEALIFT CONVERSION SHIPS CLASS. 0 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.