The Subplate Assembly,valve, cataloged under National Stock Number 4820-01-423-7635, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Sargent Aerospace & Defense, Llc Dba Sargent Controls & Aerospace Div Sargent Controls & Aerospace. Government technical data includes 2 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-423-7635 |
| Primary Part Number | 21556-400-1 |
| Item Name | Subplate Assembly,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Sargent Aerospace & Defense, Llc Dba Sargent Controls & Aerospace Div Sargent Controls & Aerospace |
| Status | ACTIVE |
| Surface Treatment | ANODIZE |
| Material | ALUMINUM ALLOY |
| 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 |
|---|---|
| 21556-400-1 PRIMARY | Sargent Aerospace & Defense, Llc Dba Sargent Controls & Aerospace Div Sargent Controls & Aerospace (USA) |
| Reference | Meaning |
|---|---|
| 21556-400 | D/9 Drawing number reference only Sargent Aerospace & Defense, Llc Dba Sargent Controls & Aerospace Div Sargent Controls & Aerospace |
NSN 4820-01-423-7635 is a Subplate Assembly,valve, manufactured by Sargent Aerospace & Defense, Llc Dba Sargent Controls & Aerospace Div Sargent Controls & Aerospace, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-423-7635 has 1 manufacturer part number on file: 21556-400-1 (Sargent Aerospace & Defense, Llc Dba Sargent Controls & Aerospace Div Sargent Controls & Aerospace).
Key specifications for 21556-400-1: Overall Length: 2.250 INCHES NOMINAL IN; Overall Width: 2.250 INCHES NOMINAL IN; Surface Treatment: ANODIZE; End Item Identification: SEAWOLF CLASS SSN.. 2 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.