The Valve,expansion, cataloged under National Stock Number 4820-01-688-3735, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Boyd Niagara, Llc. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Item Name | Valve,expansion |
| FSC / FSG | 4820 — Valves, Nonpowered (FSG 48) |
| Manufacturers | Boyd Niagara, Llc (CAGE 61228) |
| Parameter | Value |
|---|---|
| NSN | 4820-01-688-3735 |
| Primary Part Number | 40031A |
| Item Name | Valve,expansion |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Boyd Niagara, Llc |
| Status | ACTIVE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL Q — CCL Item — Commerce Control List |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 44593A FIND 9 | Boyd Niagara, Llc (USA) |
| 40031A PRIMARY | Boyd Niagara, Llc (USA) |
| Reference | Meaning |
|---|---|
| 44593A | D/9 Drawing number reference only Boyd Niagara, Llc |
NSN 4820-01-688-3735 is a Valve,expansion, manufactured by Boyd Niagara, Llc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-688-3735 has 2 manufacturer part numbers on file: 44593A FIND 9 (Boyd Niagara, Llc), 40031A (Boyd Niagara, Llc).
1 possible match (shared part number, not a government interchangeability claim): 4420-01-689-4207. Verify interchangeability with system specifications before substitution.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
NSN 4820-01-688-3735 has DEMIL Code Q. Demilitarization may be required before disposal or transfer to non-military entities.
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.