fittings › boss reducers
AN919-3J
Aeronautical Standard Boss Reducer
Description
Reducer
Specifications
| Alternate Item Number | AS5174J0504 |
|---|---|
| Alternate Part Number | AS5174J0504 |
| Connection Style | Flared with gasket seal (boss) all ends |
| Connection Type | Flare Type, Threaded external boss all ends |
| Dimension E | 0.750 in |
| Dimension S | 39/64 in |
| Dimension W | 1 23/64 in |
| Flare Angle | 37 º |
| Industry Standards/Certification | AN919 |
| Material | CRES |
| Material Specification | 66 federal standard single material response |
| NIIN | 00-911-7128 |
| NSN | 4730-00-911-7128 |
| Nominallength | 1.359 |
| Surface Treatment | Passivate |
| Surface Treatment Specification | Mil-s-5002 military specification single treatment response inside, Type 2 military specification single treatment response outside e300 mil-f-14072 |
| Thread Class | 3a all ends |
| Thread Series | UNF |
| Thread Series Designator | Unf (fine thread) 2nd end, Unjf (fine thread with external controlled root radius) 1st end |
| Thread Size | 0.438 inches 2nd end, 0.500 inches 1st end |
| Thread T (Large End (Reference)) | 1/2-20 |
| Thread T (Small End (Reference)) | 7/16-20 |
| Tube Outside Diameter (Large End) | 5/16 in |
| Tube Outside Diameter (Small End) | 1/4 in |
| Weight | .005 lb |
Cross-reference
Interchangeable
Parts that share a National Stock Number or are listed as an alternate for AN919-3J — functionally equivalent.
- AS5174J0504 Listed alternate 7/16 in · CRES
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Catalog data updated 2026-07-05. Report a data error