The Nut,tube Coupling, cataloged under National Stock Number 4730-01-181-1122, is classified within Federal Supply Class 4730 (Hose, Pipe, Tube, Lubrication, and Railing Fittings) of the Pipe, Tubing, Hose, and Fittings group. Government technical data includes 14 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4730-01-181-1122 |
| Item Name | Nut,tube Coupling |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Status | ACTIVE |
| Length to Shoulder | 0.440 INCHES NOMINAL IN |
| Width Across Flats | 0.625 INCHES NOMINAL IN |
| Thread Series | UNF |
| Seat Angle | 45.0 DEGREES NOMINAL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.438 INCHES IN |
| Nut Height | 0.590 INCHES NOMINAL IN |
| Nut Style | TUBE COUPLING |
| Thread Class | 2B |
| Thread Quantity Per Inch | 20 |
| Material | COPPER ALLOY OVERALL |
| Fabrication Method | FORGED |
| Smallest Inside Diameter | 0.255 INCHES MINIMUM AND 0.260 INCHES MAXIMUM IN |
| Nominal Tube Outside Diameter | 0.250 INCHES IN |
| 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 |
|---|---|
| 503-4556027 ITEM 34 | 5/9 Secondary reference Huntington Ingalls Inc Div Newport News Shipbuilding |
| 2670-57 | 5/9 Secondary reference Huntington Ingalls Inc Div Newport News Shipbuilding |
| 2670-57 ITEM 34 | 3/1 Design control — primary reference Huntington Ingalls Inc Div Newport News Shipbuilding |
NSN 4730-01-181-1122 is a Nut,tube Coupling, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
Key specifications for 4730-01-181-1122: Length to Shoulder: 0.440 INCHES NOMINAL IN; Width Across Flats: 0.625 INCHES NOMINAL IN; Thread Series: UNF; Seat Angle: 45.0 DEGREES NOMINAL. 14 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.