The Valve,check, cataloged under National Stock Number 4820-01-021-8371, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is The Boeing Company. Government technical data includes 18 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-01-021-8371 |
| Primary Part Number | A15HS017-2 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | The Boeing Company |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | FLARELESS SECOND END |
| Connection Style | FLARELESS FIRST END |
| Mounting Position | HORIZONTAL |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED EXTERNAL TUBE SECOND END |
| Style Designator | STRAIGHT THRU |
| Nominal Outside Diameter Tube Accommodated | 0.375 INCHES FIRST END IN |
| Nominal Outside Diameter Tube Accommodated | 0.250 INCHES SECOND END IN |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Seat Angle | 12.0 DEGREES SECOND END |
| Seat Angle | 12.0 DEGREES FIRST END |
| Disk Loading Method | SPRING |
| Surface Treatment | PASSIVATE |
| Thread Class | 3A FIRST END A |
| Thread Class | 3A SECOND END A |
| Material | STEEL CORROSION RESISTING OVERALL |
| 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 |
|---|---|
| A15HS017-2 | The Boeing Company (USA) |
| Reference | Meaning |
|---|---|
| 4C2856-1 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-021-8371 is a Valve,check, manufactured by The Boeing Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-021-8371 has 1 manufacturer part number on file: A15HS017-2 (The Boeing Company).
Key specifications for A15HS017-2: Flow Control Device: POPPET; Connection Style: FLARELESS SECOND END; Connection Style: FLARELESS FIRST END; Mounting Position: HORIZONTAL. 18 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.