The Nut,tube Coupling, cataloged under National Stock Number 4730-00-367-8100, 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 Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney. Government technical data includes 16 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4730-00-367-8100 |
| Primary Part Number | ST2121-04 |
| Item Name | Nut,tube Coupling |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney |
| Status | ACTIVE |
| Width Across Flats | 0.553 INCHES MINIMUM AND 0.564 INCHES MAXIMUM IN |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Hole Configuration Style | CONFIGURATION B |
| Material Document and Classification | AMS5646 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.438 INCHES IN |
| Nut Height | 0.600 INCHES MINIMUM AND 0.620 INCHES MAXIMUM IN |
| Drilled Hole Diameter | 0.057 INCHES MINIMUM AND 0.062 INCHES MAXIMUM IN |
| Nut Style | TUBE COUPLING |
| Thread Class | 3B |
| Thread Quantity Per Inch | 20 |
| Material | STEEL CORROSION RESISTING OVERALL |
| Fabrication Method | MACHINED |
| Smallest Inside Diameter | 0.092 INCHES MINIMUM AND 0.097 INCHES MAXIMUM IN |
| Nominal Tube Outside Diameter | 0.250 INCHES IN |
| Hole Type and Quantity | 2 DRILLED |
| 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 |
|---|---|
| ST2121-04 PRIMARY | Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney (USA) |
| Reference | Meaning |
|---|---|
| 4730PL0741555 | 6/9 Informative reference only Jednolity Indeks Materialowy - Uniform Material Index |
| ST2121-04 | 5/9 Secondary reference Turbo Power & Marine System Inc Sub of United Technologies Corp |
| ST2121-04 | 5/9 Secondary reference Comet Mfg Co Inc |
NSN 4730-00-367-8100 is a Nut,tube Coupling, manufactured by Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-00-367-8100 has 1 manufacturer part number on file: ST2121-04 (Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney).
1 possible match (shared part number, not a government interchangeability claim): 4730-01-669-4777. Verify interchangeability with system specifications before substitution.
Key specifications for ST2121-04: Width Across Flats: 0.553 INCHES MINIMUM AND 0.564 INCHES MAXIMUM IN; Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF); Hole Configuration Style: CONFIGURATION B; Material Document and Classification: AMS5646 ASSN STD SINGLE MATERIAL RESPONSE OVERALL. 16 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.