The Nut,tube Coupling, cataloged under National Stock Number 4730-01-543-0356, is classified within Federal Supply Class 4730 (Hose, Pipe, Tube, Lubrication, and Railing Fittings) of the Pipe, Tubing, Hose, and Fittings group. The manufacturer of record is Sae International Dba Sae International. Government technical data includes 15 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through both NSN and commercial part number lookups. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4730-01-543-0356 |
| Primary Part Number | MS21921V4P |
| Item Name | Nut,tube Coupling |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | Sae International Dba Sae International |
| Status | ACTIVE |
| Length to Shoulder | 0.537 INCHES MINIMUM AND 0.557 INCHES MAXIMUM IN |
| Width Across Flats | 0.562 INCHES NOMINAL IN |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Seat Angle | 45.0 DEGREES NOMINAL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.438 INCHES IN |
| Specification/standard Data | 81343 - AS21921 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| Nut Height | 0.710 INCHES MINIMUM AND 0.730 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OVERALL |
| Nut Style | TUBE COUPLING |
| Thread Class | 3B |
| Thread Quantity Per Inch | 20 |
| Material | STEEL OVERALL |
| Smallest Inside Diameter | 0.300 INCHES MINIMUM AND 0.305 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 |
| Part Number | Manufacturer |
|---|---|
| MS21921V4P PRIMARY | Sae International Dba Sae International (USA) |
| Reference | Meaning |
|---|---|
| AS21921 | 5/9 Secondary reference U.S. Government activity |
| AS21921 | 5/9 Secondary reference Sae International Dba Sae International |
| AS18280 | 5/9 Secondary reference U.S. Government activity |
| SAE-AS18280 | 3/1 Design control — primary reference Sae International Dba Sae International |
| MS21921V4P | 5/9 Secondary reference U.S. Government activity |
| 4730015430356 | 6/9 Informative reference only E.c.a Etablissement Central Des Approvisionnements Des Forces Armees Royales |
| AS18280 | 5/9 Secondary reference Sae International Dba Sae International |
NSN 4730-01-543-0356 is a Nut,tube Coupling, manufactured by Sae International Dba Sae International, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-01-543-0356 has 1 manufacturer part number on file: MS21921V4P (Sae International Dba Sae International).
Key specifications for MS21921V4P: Length to Shoulder: 0.537 INCHES MINIMUM AND 0.557 INCHES MAXIMUM IN; Width Across Flats: 0.562 INCHES NOMINAL IN; Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF); Seat Angle: 45.0 DEGREES NOMINAL. 15 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.