The Nut,union, cataloged under National Stock Number 4730-00-277-3343, 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 15 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 6 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4730-00-277-3343 |
| Item Name | Nut,union |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Status | ACTIVE |
| Width Across Flats | 3.625 INCHES NOMINAL IN |
| Shoulder Step Width | 0.406 INCHES NOMINAL IN |
| Shoulder Width | 1.406 INCHES NOMINAL IN |
| Thread Series | UN |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 2.876 INCHES IN |
| Nut Diameter | 3.625 INCHES NOMINAL IN |
| Nut Height | 2.875 INCHES NOMINAL IN |
| Nut Style | ROUND |
| Thread Class | 2B |
| Thread Quantity Per Inch | 12 |
| Material | NICKEL ALLOY OVERALL |
| Smallest Inside Diameter | 2.063 INCHES NOMINAL IN |
| Reference Number Differentiating Characteristics | AS DIFFERENTIATED BY THD SIZE |
| Shoulder Seat Diameter | 2.734 INCHES NOMINAL 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 |
|---|---|
| 8600-208PC23 | 5/2 Secondary reference U.S. Government activity |
| 15-01-7514 | 5/2 Secondary reference U.S. Government activity |
| 5000S4823-841337PC4 | 3/1 Design control — primary reference U.S. Government activity |
NSN 4730-00-277-3343 is a Nut,union, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
6 possible matches (shared part number, not a government interchangeability claim): 4730-00-277-3344, 4730-00-277-3345, 4730-00-277-3346. Verify interchangeability with system specifications before substitution.
Key specifications for 4730-00-277-3343: Width Across Flats: 3.625 INCHES NOMINAL IN; Shoulder Step Width: 0.406 INCHES NOMINAL IN; Shoulder Width: 1.406 INCHES NOMINAL IN; Thread Series: UN. 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.