The Tee,tube to Boss, cataloged under National Stock Number 4730-00-181-9491, 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 The Boeing Company Div Defense. Government technical data includes 29 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government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 | 4730-00-181-9491 |
| Primary Part Number | 7M137D20-20-16 |
| Item Name | Tee,tube to Boss |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Connection Style | FLARED (TUBE) SECOND END |
| Connection Style | GASKET SEAL (BOSS) THIRD END |
| Connection Style | FLARED (TUBE) FIRST END |
| Connection Type | THREADED INTERNAL BOSS THIRD END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END BULKHEAD |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED EXTERNAL TUBE SECOND END |
| Nominal Outside Diameter Tube Accommodated | 1.250 INCHES FIRST END IN |
| Nominal Outside Diameter Tube Accommodated | 1.250 INCHES SECOND END IN |
| Leg Length | 1.742 INCHES NOMINAL THIRD END IN |
| Leg Length | 2.273 INCHES NOMINAL SECOND END IN |
| Leg Length | 3.054 INCHES NOMINAL FIRST END IN |
| Nominal Thread Size | 1.625 INCHES SECOND END IN |
| Nominal Thread Size | 1.625 INCHES FIRST END IN |
| Nominal Thread Size | 1.312 INCHES THIRD END IN |
| Nominal Thread Size | 1.625 INCHES SECOND END BULKHEAD IN |
| Seat Angle | 37.0 DEGREES FIRST END |
| Seat Angle | 37.0 DEGREES SECOND END |
| Specification/standard Data | 76301-7-137 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| Surface Treatment | ANODIZE OVERALL |
| Thread Class | 3A FIRST END A |
| Thread Class | 3A FIRST END BULKHEAD A |
| Thread Class | 3A SECOND END A |
| Thread Class | 3B THIRD END |
| Thread Quantity Per Inch | 12 FIRST END BULKHEAD |
| Thread Quantity Per Inch | 12 ALL ENDS |
| Material | ALUMINUM ALLOY BODY |
| Thread Series Designator | UNIFIED NATIONAL JOINT (UNJ) FIRST END BULKHEAD |
| Thread Series Designator | UNIFIED NATIONAL JOINT (UNJ) ALL ENDS |
| 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 |
|---|---|
| 7M137D20-20-16 PRIMARY | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| 7M137 | 5/1 Secondary reference The Boeing Company Div Defense |
NSN 4730-00-181-9491 is a Tee,tube to Boss, manufactured by The Boeing Company Div Defense, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-00-181-9491 has 1 manufacturer part number on file: 7M137D20-20-16 (The Boeing Company Div Defense).
3 possible matches (shared part number, not a government interchangeability claim): 4730-00-241-8309, 4730-00-849-2441, 4730-01-310-1159. Verify interchangeability with system specifications before substitution.
Key specifications for 7M137D20-20-16: Connection Style: FLARED (TUBE) SECOND END; Connection Style: GASKET SEAL (BOSS) THIRD END; Connection Style: FLARED (TUBE) FIRST END; Connection Type: THREADED INTERNAL BOSS THIRD END. 29 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.