The Valve Assembly,manifold, cataloged under National Stock Number 4820-01-446-5908, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is F.s. Welsford Company. Government technical data includes 8 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-446-5908 |
| Primary Part Number | FSW 666.5625 |
| Item Name | Valve Assembly,manifold |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | F.s. Welsford Company |
| Status | ACTIVE |
| Valve Quantity | 3 |
| Connection Type | THREADED INTERNAL TUBE |
| End Connection Quantity | 2 |
| Nominal Thread Size | 0.562 INCHES IN |
| Body Material | STEEL CORROSION RESISTING |
| Thread Class | 2B |
| Thread Series Designator | UNF |
| Valve Operation Method | MANUAL |
| 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 |
|---|---|
| HM53-55 | Richards Industries Valve Group Hex Valve Div (USA) |
| FSW 666.5625 PRIMARY | F.s. Welsford Company (USA) |
| Reference | Meaning |
|---|---|
| FSW 666B.5625 | C/1 Advisory reference — outside the item-of-supply concept F.s. Welsford Company |
| FSW53666-5625 | 5/9 Secondary reference F.s. Welsford Company |
NSN 4820-01-446-5908 is a Valve Assembly,manifold, manufactured by F.s. Welsford Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-446-5908 has 2 manufacturer part numbers on file: HM53-55 (Richards Industries Valve Group Hex Valve Div), FSW 666.5625 (F.s. Welsford Company).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-492-0937. Verify interchangeability with system specifications before substitution.
Key specifications for FSW 666.5625: Valve Quantity: 3; Connection Type: THREADED INTERNAL TUBE; End Connection Quantity: 2; Nominal Thread Size: 0.562 INCHES IN. 8 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.