The Valve,check, cataloged under National Stock Number 4820-01-278-8638, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp. Government technical data includes 19 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-278-8638 |
| Primary Part Number | 70651-03301-043 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | FLARELESS SECOND END |
| Connection Style | PLAIN (TUBE) FIRST END |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED EXTERNAL TUBE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 3000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.438 INCHES SECOND END IN |
| Nominal Thread Size | 0.750 INCHES FIRST END IN |
| Seat Angle | 24.0 DEGREES ALL ENDS |
| Disk Loading Method | SPRING |
| Media for Which Designed | HYDRAULIC FLUID, MINERAL BASE SINGLE RESPONSE |
| Thread Class | 3A ALL ENDS A |
| Thread Quantity Per Inch | 16 FIRST END |
| Thread Quantity Per Inch | 20 SECOND END |
| Material | ALUMINUM ALLOY BODY |
| Thread Series Designator | UNIFIED NATIONAL JOINT (UNJ) ALL ENDS |
| Valve Operation Method | AUTOMATIC |
| 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 |
|---|---|
| 70651-03301-043 PRIMARY | Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp (USA) |
| Reference | Meaning |
|---|---|
| 4820PL1943720 | 6/9 Informative reference only Jednolity Indeks Materialowy - Uniform Material Index |
| 70651-03301 | D/9 Drawing number reference only Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp |
| 70651-03301-042 | 5/9 Secondary reference Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp |
NSN 4820-01-278-8638 is a Valve,check, manufactured by Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-278-8638 has 1 manufacturer part number on file: 70651-03301-043 (Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp).
Key specifications for 70651-03301-043: Flow Control Device: POPPET; Connection Style: FLARELESS SECOND END; Connection Style: PLAIN (TUBE) FIRST END; Mounting Position: HORIZONTAL OR VERTICAL. 19 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.