The Valve,check, cataloged under National Stock Number 4820-01-578-3750, 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23 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 4820-01-578-3750 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Flange Shape | RECTANGULAR WITH HOLES FIRST END |
| Flange Face Design | PLAIN FIRST END |
| Surface Treatment Document and Classification | MIL-A-8625, TY 2 MIL SPEC SINGLE TREATMENT RESPONSE |
| Connection Style | BEADED (HOSE) SECOND END |
| Nominal Length | 2.440 INCHES FIRST END IN |
| Mounting Position | HORIZONTAL |
| Connection Type | UNTHREADED EXTERNAL HOSE SECOND END |
| Connection Type | FLANGE FIRST END |
| Style Designator | STRAIGHT THRU |
| Material Document and Classification | QQ-A-6, ALLOY 2024 FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Bolt Hole Nominal Diameter | 0.285 INCHES FIRST END IN |
| Operating Pressure | 90.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Maximum Operating Temp | 450.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Center to Center Nominal Distance Between Bolt Holes Along Width | 1.812 INCHES FIRST END IN |
| Bolt Hole Quantity | 4 FIRST END |
| Surface Treatment | ANODIZE |
| Nominal Width | 2.440 INCHES FIRST END IN |
| Center to Center Nominal Distance Between Bolt Holes Along Length | 1.812 INCHES FIRST END IN |
| Media for Which Designed | AIR SINGLE RESPONSE |
| Material | ALUMINUM ALLOY 2024 OVERALL |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 0.250 INCHES FIRST END IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| CV99-337 | 3/2 Design control — primary reference U.S. Government activity |
| ST7M347-3 | 7/2 Vendor item drawing reference The Boeing Company Div Defense |
NSN 4820-01-578-3750 is a Valve,check, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-578-3750: Flow Control Device: POPPET; Flange Shape: RECTANGULAR WITH HOLES FIRST END; Flange Face Design: PLAIN FIRST END; Surface Treatment Document and Classification: MIL-A-8625, TY 2 MIL SPEC SINGLE TREATMENT RESPONSE. 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.
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.