The Valve,check, cataloged under National Stock Number 4820-01-212-6791, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is The Walworth Company. Government technical data includes 7 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 4 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-212-6791 |
| Primary Part Number | W428 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | The Walworth Company |
| Status | ACTIVE |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 1.500 INCHES ALL ENDS IN |
| Media for Which Designed | WATER-OIL-GAS SINGLE RESPONSE |
| Material | COPPER OVERALL |
| Thread Series Designator | NPTF 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 |
|---|---|
| W428 PRIMARY | The Walworth Company (USA) |
| Reference | Meaning |
|---|---|
| 3428 | 5/9 Secondary reference The Walworth Company |
NSN 4820-01-212-6791 is a Valve,check, manufactured by The Walworth Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-212-6791 has 1 manufacturer part number on file: W428 (The Walworth Company).
4 possible matches (shared part number, not a government interchangeability claim): 4320-01-248-7924, 5940-01-300-6369, 1940-01-481-1317. Verify interchangeability with system specifications before substitution.
Key specifications for W428: Connection Type: THREADED INTERNAL PIPE ALL ENDS; Thread Direction: RIGHT-HAND ALL ENDS; Nominal Thread Size: 1.500 INCHES ALL ENDS IN; Media for Which Designed: WATER-OIL-GAS SINGLE RESPONSE. 7 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.