The Valve,check, cataloged under National Stock Number 4820-01-166-7131, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 26 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-166-7131 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Surface Treatment Document and Classification | MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE |
| Connection Style | EXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END |
| Connection Style | GASKET SEAL (BOSS) FIRST END |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED INTERNAL BOSS FIRST END |
| Connection Type | THREADED EXTERNAL BOSS SECOND END |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 120.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 1.062 INCHES FIRST END IN |
| Nominal Thread Size | 1.062 INCHES SECOND END IN |
| Seat Angle | 37.0 DEGREES SECOND END |
| Maximum Operating Temp | 450.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE |
| Media for Which Designed | AIR SINGLE RESPONSE |
| Thread Class | 3A SECOND END A |
| Thread Class | 3B FIRST END |
| Thread Quantity Per Inch | 12 SECOND END |
| Thread Quantity Per Inch | 12 FIRST END |
| Material | ALUMINUM ALLOY 2024 BODY |
| Thread Series Designator | UNIFIED NATIONAL JOINT (UNJ) SECOND END |
| Thread Series Designator | UNIFIED NATIONAL JOINT (UNJ) FIRST 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 |
|---|---|
| 12C146 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-166-7131 is a Valve,check, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-166-7131: Flow Control Device: DISK; Surface Treatment Document and Classification: MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE; Connection Style: EXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END; Connection Style: GASKET SEAL (BOSS) FIRST END. 26 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 4820-01-166-7131 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.