The Valve,check, cataloged under National Stock Number 4820-01-185-1133, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is The Walworth Company. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Item Name | Valve,check |
| FSC / FSG | 4820 — Valves, Nonpowered (FSG 48) |
| Manufacturers | The Walworth Company (CAGE 63686) |
| Parameter | Value |
|---|---|
| NSN | 4820-01-185-1133 |
| Primary Part Number | 420WS 2 1/2 IN |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | The Walworth Company |
| Status | ACTIVE |
| 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 |
|---|---|
| 420WS 2 1/2 IN PRIMARY | The Walworth Company (USA) |
| Reference | Meaning |
|---|---|
| DS-47871 | 5/9 Secondary reference The Walworth Company |
| 420SW 2 1/2 IN | 5/9 Secondary reference The Walworth Company |
| 151501.450 | 5/9 Secondary reference W and O Supply |
NSN 4820-01-185-1133 is a Valve,check, manufactured by The Walworth Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-185-1133 has 1 manufacturer part number on file: 420WS 2 1/2 IN (The Walworth Company).
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.