The Seat,valve, cataloged under National Stock Number 4820-01-415-9557, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Naval Sea Systems Command. Government technical data includes 6 specifications, cited from the U.S. Government catalog. The record lists 7 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 4 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-415-9557 |
| Primary Part Number | 218006203 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| Body Outside Diameter | 2.122 INCHES NOMINAL IN |
| Style Designator | PLAIN |
| Body Inside Diameter | 1.250 INCHES NOMINAL IN |
| Seat Radius | 0.470 INCHES NOMINAL IN |
| Material | PLASTIC POLYAMIDE NYLON SEAT |
| Seating Surface Shape | RADIAL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 211067931 | Naval Sea Systems Command (USA) |
| 556-6406594-MPLA-C12 | Naval Sea Systems Command (USA) |
| DF2300-4657 FN MPLA-A12 | Huntington Ingalls Inc Div Newport News Shipbuilding (USA) |
| 556-6406594-MPLA-D12 | Naval Sea Systems Command (USA) |
| 556-6406594-MPLA-A12 | Naval Sea Systems Command (USA) |
| 218006203 PRIMARY | Naval Sea Systems Command (USA) |
| 556-6406594-MPLA-B12 | Naval Sea Systems Command (USA) |
| Reference | Meaning |
|---|---|
| 6406594 | D/9 Drawing number reference only Naval Sea Systems Command |
| C791-5301 FN MPLA-A12 | 5/2 Secondary reference U.S. Government activity |
| C791-5301 | D/9 Drawing number reference only U.S. Government activity |
| DF2300-4657 | D/9 Drawing number reference only Huntington Ingalls Inc Div Newport News Shipbuilding |
NSN 4820-01-415-9557 is a Seat,valve, manufactured by Naval Sea Systems Command, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-415-9557 has 7 manufacturer part numbers on file: 211067931 (Naval Sea Systems Command), 556-6406594-MPLA-C12 (Naval Sea Systems Command), DF2300-4657 FN MPLA-A12 (Huntington Ingalls Inc Div Newport News Shipbuilding), 556-6406594-MPLA-D12 (Naval Sea Systems Command), 556-6406594-MPLA-A12 (Naval Sea Systems Command) and 2 more.
4 possible matches (shared part number, not a government interchangeability claim): 4820-01-415-9563, 4820-01-416-1662, 4730-01-417-1580. Verify interchangeability with system specifications before substitution.
Key specifications for 218006203: Overall Height: 0.375 INCHES NOMINAL IN; Body Outside Diameter: 2.122 INCHES NOMINAL IN; Style Designator: PLAIN; Body Inside Diameter: 1.250 INCHES NOMINAL IN. 6 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.