The Valve,check, cataloged under National Stock Number 4820-00-627-4407, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Instruments and Flight Research, Inc.. Government technical data includes 24 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-00-627-4407 |
| Primary Part Number | 516434-3 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Instruments and Flight Research, Inc. |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Surface Treatment Document and Classification | MIL-A-8625,TY 1 MIL SPEC SINGLE TREATMENT RESPONSE |
| Connection Style | FLARED (TUBE) ALL ENDS |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED EXTERNAL TUBE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Material Document and Classification | QQ-A-225/6, ALLOY 2024, T4 FED SPEC SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | QQ-A-225/6, ALLOY 2024, T4 FED SPEC SINGLE MATERIAL RESPONSE SEAT |
| Operating Pressure | 3000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM FIRST RESPONSE LBS |
| Operating Pressure | 30000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SECOND RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.750 INCHES ALL ENDS IN |
| Seat Angle | 37.0 DEGREES ALL ENDS |
| Maximum Operating Temp | 280.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE |
| Media for Which Designed | WATER-OIL-GAS SECOND RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Thread Class | 3A ALL ENDS A |
| Material | ALUMINUM ALLOY 2024 BODY |
| Material | ALUMINUM FLOW CONTROL DEVICE |
| Material | ALUMINUM ALLOY 2024 SEAT |
| Thread Series Designator | UNF 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 |
|---|---|
| 516434-3 | Instruments and Flight Research, Inc. (USA) |
| Reference | Meaning |
|---|---|
| 259A8TT | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-00-627-4407 is a Valve,check, manufactured by Instruments and Flight Research, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-627-4407 has 1 manufacturer part number on file: 516434-3 (Instruments and Flight Research, Inc.).
Key specifications for 516434-3: Flow Control Device: POPPET; Surface Treatment Document and Classification: MIL-A-8625,TY 1 MIL SPEC SINGLE TREATMENT RESPONSE; Connection Style: FLARED (TUBE) ALL ENDS; Mounting Position: HORIZONTAL OR VERTICAL. 24 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.