The Valve,check, cataloged under National Stock Number 4820-01-043-4385, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Lourdes Industries, Inc.. Government technical data includes 16 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-043-4385 |
| Primary Part Number | L53000-2-56A |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Lourdes Industries, Inc. |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Surface Treatment Document and Classification | MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE |
| Connection Style | GROOVED (TUBE) FIRST END |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | UNTHREADED EXTERNAL TUBE FIRST END |
| Style Designator | STRAIGHT THRU |
| Material Document and Classification | QQ-A-601,ALLOY 356,T7 FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Outside Diameter Tube Accommodated | 3.500 INCHES FIRST END IN |
| Operating Pressure | 60.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Specification/standard Data | 26512-GV500MJ MANUFACTURERS STANDARD |
| Maximum Operating Temp | 350.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE |
| Media for Which Designed | WATER-OIL-GAS SINGLE RESPONSE |
| Material | ALUMINUM ALLOY OVERALL |
| 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 |
|---|---|
| L53000-2-56A PRIMARY | Lourdes Industries, Inc. (USA) |
| GV500MJ56A2 | Northrop Grumman Systems Corporation (USA) |
| Reference | Meaning |
|---|---|
| GV500MJ | 5/9 Secondary reference Northrop Grumman Systems Corporation |
NSN 4820-01-043-4385 is a Valve,check, manufactured by Lourdes Industries, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-043-4385 has 2 manufacturer part numbers on file: L53000-2-56A (Lourdes Industries, Inc.), GV500MJ56A2 (Northrop Grumman Systems Corporation).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-359-0987. Verify interchangeability with system specifications before substitution.
Key specifications for L53000-2-56A: Flow Control Device: DISK; Surface Treatment Document and Classification: MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE; Connection Style: GROOVED (TUBE) FIRST END; Mounting Position: HORIZONTAL OR VERTICAL. 16 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.