The Valve,check, cataloged under National Stock Number 4820-00-078-3528, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Eaton Corporation Dba Eaton Inoac Div Eaton. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-00-078-3528 |
| Primary Part Number | 646-16D |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Eaton Corporation Dba Eaton Inoac Div Eaton |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Surface Treatment Document and Classification | MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE |
| Connection Style | BEADED (HOSE) SECOND END |
| Connection Style | FLARED (TUBE) FIRST END |
| Style Designator | ANGLE |
| Nominal Outside Diameter Tube Accommodated | 1.000 INCHES FIRST END IN |
| Operating Pressure | 60.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 1.312 INCHES FIRST END IN |
| Seat Angle | 37.0 DEGREES FIRST END |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE |
| Media for Which Designed | FUEL/OIL, HYDROCARBON SINGLE RESPONSE |
| Thread Class | 3A FIRST END A |
| Thread Quantity Per Inch | 12 FIRST END |
| Material | ALUMINUM ALLOY FLOW CONTROL DEVICE |
| Thread Series Designator | UN FIRST END |
| 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 |
|---|---|
| 646-16D PRIMARY | Eaton Corporation Dba Eaton Inoac Div Eaton (USA) |
| Reference | Meaning |
|---|---|
| 215-33331-1 | 7/2 Vendor item drawing reference U.S. Government activity |
NSN 4820-00-078-3528 is a Valve,check, manufactured by Eaton Corporation Dba Eaton Inoac Div Eaton, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-078-3528 has 1 manufacturer part number on file: 646-16D (Eaton Corporation Dba Eaton Inoac Div Eaton).
Key specifications for 646-16D: Flow Control Device: POPPET; Surface Treatment Document and Classification: MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE; Connection Style: BEADED (HOSE) SECOND END; Connection Style: FLARED (TUBE) FIRST END. 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.