The Seat,valve, cataloged under National Stock Number 4820-00-623-8671, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Singer Valve Inc. Government technical data includes 5 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-623-8671 |
| Primary Part Number | A0365-3 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Singer Valve Inc |
| Status | ACTIVE |
| Flange Diameter | 3.000 INCHES NOMINAL IN |
| Body Outside Diameter | 2.750 INCHES NOMINAL IN |
| Material Document and Classification | QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Material | NICKEL ALLOY OVERALL |
| 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 |
| Part Number | Manufacturer |
|---|---|
| A0365-3 PRIMARY | Singer Valve Inc (CAN) |
| 26100365903 | Aircraft Appliances and Equipment Limited Div Aircraft Appliances and Equipment Ltd. (CAN) |
NSN 4820-00-623-8671 is a Seat,valve, manufactured by Singer Valve Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-623-8671 has 2 manufacturer part numbers on file: A0365-3 (Singer Valve Inc), 26100365903 (Aircraft Appliances and Equipment Limited Div Aircraft Appliances and Equipment Ltd.).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-151-3730. Verify interchangeability with system specifications before substitution.
Key specifications for A0365-3: Flange Diameter: 3.000 INCHES NOMINAL IN; Overall Height: 1.875 INCHES NOMINAL IN; Body Outside Diameter: 2.750 INCHES NOMINAL IN; Material Document and Classification: QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE OVERALL. 5 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.