The Tee,tube, cataloged under National Stock Number 4730-00-997-1446, 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 Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems. Government technical data includes 25 specifications, cited from the U.S. Government catalog. The record lists 5 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4730-00-997-1446 |
| Primary Part Number | 21T187-8-8 |
| Item Name | Tee,tube |
| FSC / FSG | 4730 / 47 — Hose, Pipe, Tube, Lubrication, and Railing Fittings |
| Manufacturer | Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems |
| Status | ACTIVE |
| Connection Style | SWIVEL NUT, FLARE (TUBE) STYLE 3 OPTIONAL END THIRD END |
| Connection Style | FLARELESS (TUBE) SECOND END |
| Connection Style | FLARELESS (TUBE) FIRST END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED EXTERNAL TUBE SECOND END |
| Connection Type | THREADED INTERNAL TUBE THIRD END |
| Nominal Outside Diameter Tube Accommodated | 0.500 INCHES SECOND END IN |
| Nominal Outside Diameter Tube Accommodated | 0.500 INCHES THIRD END IN |
| Nominal Outside Diameter Tube Accommodated | 0.500 INCHES FIRST END IN |
| Leg Length | 1.875 INCHES NOMINAL FIRST END IN |
| Leg Length | 1.312 INCHES NOMINAL SECOND END IN |
| Leg Length | 1.688 INCHES NOMINAL THIRD END IN |
| Nominal Thread Size | 0.750 INCHES SECOND END IN |
| Nominal Thread Size | 0.750 INCHES THIRD END IN |
| Nominal Thread Size | 0.750 INCHES FIRST END IN |
| Seat Angle | 45.0 DEGREES THIRD END |
| Seat Angle | 12.0 DEGREES SECOND END |
| Seat Angle | 12.0 DEGREES FIRST END |
| Thread Class | 3A FIRST END A |
| Thread Class | 3A SECOND END A |
| Thread Class | 3B THIRD END |
| Material | STEEL OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) FIRST END |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) THIRD END |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) SECOND END |
| 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 |
|---|---|
| 21T187-8-8 | Sps Technologies, Llc Dba Airdrome Precision Components (USA) |
| 21T187-8-8 PRIMARY | Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems (USA) |
| 21T187-8-8 | Designed Metal Connections Inc Dba Permaswage Usa Div Permaswage, a Pcc Company (USA) |
| 21T187-8-8 PRIMARY | Eaton Aeroquip Llc Dba Jackson North 1 Div Fluid and Electrical Distribution (USA) |
| 21T187-8-8 | Northrop Grumman Systems Corporation (USA) |
| Reference | Meaning |
|---|---|
| 21T187 | D/9 Drawing number reference only Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems |
| 21T187-8-8 | 5/9 Secondary reference Northrop Grumman Technical Services, Inc. Dba Defense Systems Sector |
| 21T187-8-8 | 5/2 Secondary reference U.S. Government activity |
NSN 4730-00-997-1446 is a Tee,tube, manufactured by Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems, classified under FSC 4730, Hose, Pipe, Tube, Lubrication, and Railing Fittings. Status: active.
NSN 4730-00-997-1446 has 5 manufacturer part numbers on file: 21T187-8-8 (Sps Technologies, Llc Dba Airdrome Precision Components), 21T187-8-8 (Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems), 21T187-8-8 (Designed Metal Connections Inc Dba Permaswage Usa Div Permaswage, a Pcc Company), 21T187-8-8 (Eaton Aeroquip Llc Dba Jackson North 1 Div Fluid and Electrical Distribution), 21T187-8-8 (Northrop Grumman Systems Corporation).
1 possible match (shared part number, not a government interchangeability claim): 4730-01-054-3882. Verify interchangeability with system specifications before substitution.
Key specifications for 21T187-8-8: Connection Style: SWIVEL NUT, FLARE (TUBE) STYLE 3 OPTIONAL END THIRD END; Connection Style: FLARELESS (TUBE) SECOND END; Connection Style: FLARELESS (TUBE) FIRST END; Connection Type: THREADED EXTERNAL TUBE FIRST END. 25 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.