The Valve,check, cataloged under National Stock Number 4820-01-165-1966, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 23 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-165-1966 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | EXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END |
| Connection Style | EXTERNAL SEAT FOR GASKET SEAL (BOSS) FIRST END |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED EXTERNAL BOSS FIRST END |
| Connection Type | THREADED EXTERNAL BOSS SECOND END |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 70.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.562 INCHES SECOND END IN |
| Nominal Thread Size | 0.750 INCHES FIRST END IN |
| Seat Angle | 37.0 DEGREES FIRST END |
| Seat Angle | 37.0 DEGREES SECOND END |
| Maximum Operating Temp | 525.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Thread Class | 3A FIRST END A |
| Thread Class | 3A SECOND END A |
| Test Data Document | 43999-LE284-0031 DRAWING (THIS IS THE BASIC GOVERNING DRAWING, SUCH AS A CONTRACTOR DRAWING, ORIGINAL EQUIPMENT MANUFACTURER DRAWING, ETC.; EXCLUDES ANY SPECIFICATION, STANDARD OR OTHER DOCUMENT THAT MAY BE REFERENCED IN A BASIC GOVERNING DRAWING) |
| Material | STEEL CORROSION RESISTING BODY |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) FIRST END |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) SECOND END |
| Valve Operation Method | AUTOMATIC |
| 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 |
| Reference | Meaning |
|---|---|
| 4C3050 | 3/2 Design control — primary reference U.S. Government activity |
| LE284-0031-0001 | 7/2 Vendor item drawing reference The Boeing Company Div Legacy Am&m |
NSN 4820-01-165-1966 is a Valve,check, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-165-1966: Flow Control Device: POPPET; Connection Style: EXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END; Connection Style: EXTERNAL SEAT FOR GASKET SEAL (BOSS) FIRST END; Mounting Position: HORIZONTAL OR VERTICAL. 23 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.
NSN 4820-01-165-1966 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.