The Reducer,tube, cataloged under National Stock Number 4730-01-299-9496, 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 Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier. Government technical data includes 17 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4730-01-299-9496 |
| Primary Part Number | 1551AS779-1 |
| Item Name | Reducer,tube |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
| Status | ACTIVE |
| Furnished Items and Quantity | 1 TUBE COUPLING NUT |
| Nominal Overall Length | 1.406 INCHES IN |
| Criticality Code Justification | FEAT |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED EXTERNAL TUBE SECOND END |
| Nominal Outside Diameter Tube Accommodated | 0.375 INCHES FIRST END IN |
| Nominal Outside Diameter Tube Accommodated | 0.250 INCHES SECOND END IN |
| Operating Pressure | 11700.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Nominal Thread Size | 0.438 INCHES SECOND END IN |
| Nominal Thread Size | 0.563 INCHES FIRST END IN |
| Seat Angle | 12.0 DEGREES FIRST END |
| Thread Class | 2A SECOND END A |
| Thread Class | 2A FIRST END A |
| Material | STEEL CORROSION RESISTING OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) FIRST END |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) SECOND END |
| Reducer Type | CONCENTRIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | Y |
| Part Number | Manufacturer |
|---|---|
| SS-44M-A-400 | Swagelok Co (USA) |
| 1551AS779-1 PRIMARY | Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier (USA) |
| Reference | Meaning |
|---|---|
| SS-44M-A-400 | 5/9 Secondary reference Cajon Co |
| SS-44M-A-400 | 5/9 Secondary reference Sno-Trik Co Div of Crawford Fitting Co |
| 1551AS779 | D/9 Drawing number reference only Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier |
NSN 4730-01-299-9496 is a Reducer,tube, manufactured by Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-01-299-9496 has 2 manufacturer part numbers on file: SS-44M-A-400 (Swagelok Co), 1551AS779-1 (Naval Air Systems Command Managed Original Design Activity Not Material/parts Supplier).
2 possible matches (shared part number, not a government interchangeability claim): 5975-01-324-5255, 4730-01-490-6472. Verify interchangeability with system specifications before substitution.
Key specifications for 1551AS779-1: Furnished Items and Quantity: 1 TUBE COUPLING NUT; Nominal Overall Length: 1.406 INCHES IN; Criticality Code Justification: FEAT; Connection Type: THREADED EXTERNAL TUBE FIRST END. 17 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.