The Valve,check, cataloged under National Stock Number 4820-00-421-3874, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 16 specifications, cited from the U.S. Government catalog. 6 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-421-3874 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | PLAIN, OPTIONAL END (PIPE) ALL ENDS |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Offset Distance | 1.125 INCHES IN |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.375 INCHES SECOND END IN |
| Nominal Thread Size | 0.375 INCHES FIRST END IN |
| Nominal Thread Size | 0.250 INCHES THIRD END IN |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE |
| Material | STEEL FLOW CONTROL DEVICE |
| Material | STEEL STEM |
| Material | ALUMINUM ALLOY BODY |
| Thread Series Designator | NPT 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 |
| Reference | Meaning |
|---|---|
| MHB-030-LEAH-06B | 5/9 Secondary reference Parker-Hannifin Corporation Dba Pneutronics Div Gear Pump Division |
| 989010 | 5/9 Secondary reference Bosch Automation Technology |
| 2982963 | 5/9 Secondary reference Parker-Hannifin Corporation Dba Pneutronics Div Gear Pump Division |
| MHB-030-LEAH-06B | 3/2 Design control — primary reference U.S. Government activity |
| 25725-3-3-2 | 5/9 Secondary reference Parker-Hannifin Corporation Dba Pneutronics Div Gear Pump Division |
| 2982514 | 5/9 Secondary reference Parker-Hannifin Corporation Dba Pneutronics Div Gear Pump Division |
NSN 4820-00-421-3874 is a Valve,check, classified under FSC 4820, Valves, Nonpowered. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5331-00-582-7480. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-00-421-3874: Flow Control Device: DISK; Connection Style: PLAIN, OPTIONAL END (PIPE) ALL ENDS; Mounting Position: HORIZONTAL OR VERTICAL; Connection Type: THREADED INTERNAL PIPE ALL ENDS. 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.