The Nut,tube Coupling, cataloged under National Stock Number 4730-00-825-2091, 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14 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4730-00-825-2091 |
| Item Name | Nut,tube Coupling |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Status | ACTIVE |
| Length to Shoulder | 0.599 INCHES MINIMUM AND 0.619 INCHES MAXIMUM IN |
| Width Across Flats | 0.875 INCHES NOMINAL IN |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Seat Angle | 45.00 DEGREES NOMINAL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.750 INCHES IN |
| Nut Height | 0.850 INCHES MINIMUM AND 0.870 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Nut Style | TUBE COUPLING |
| Thread Class | 3B |
| Thread Quantity Per Inch | 16 |
| Material | STEEL CORROSION RESISTING OVERALL |
| Smallest Inside Diameter | 0.552 INCHES MINIMUM AND 0.557 INCHES MAXIMUM IN |
| Nominal Tube Outside Diameter | 0.500 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 |
|---|---|
| MS21921-8C | 5/9 Secondary reference Collins Engineering Corp |
| MS21921-8C | 2/2 Government specification standardization U.S. Government activity |
| MS21921-8C | 5/9 Secondary reference Designed Metal Connections Inc Dba Permaswage Usa Div Permaswage, a Pcc Company |
| MS21921-8C | 5/9 Secondary reference Dana Corp Weatherhead Div |
NSN 4730-00-825-2091 is a Nut,tube Coupling, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
Key specifications for 4730-00-825-2091: Length to Shoulder: 0.599 INCHES MINIMUM AND 0.619 INCHES MAXIMUM IN; Width Across Flats: 0.875 INCHES NOMINAL IN; Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF); Seat Angle: 45.00 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.