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AN919-4D

AN Fitting AN919-4D Reducer

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Description

Reducer

Specifications

Alternate Item Number AS5174D0602 1/
Alternate Part Number AS5174D0602
Connection Style Flared w/ gasket seal (boss) all ends
Connection Type Flare Type, Threaded external boss all ends
Dimension E 0.813 in
Dimension S 5/8 in
Dimension W 1 19/64 in
Flare Angle 37 º
Industry Standards/Certification AN919
Material Aluminum
Material Specification Qq-q-225/4,t6 fed spec single material response
NIIN 00-187-3578
NSN 4730-00-187-3578
Nominallength 1.297
Size No. Alum 4D
Size No. Steel 4
Surface Treatment Anodize
Thread Class 3a all ends
Thread Series Designator Unf 2nd end, Unjf 1st end
Thread Size 0.312 inches 2nd end, 0.562 inches 1st end
Thread T (Large End (Reference)) 9/16-18
Thread T (Small End (Reference)) 5/16-24
Tube O.D. 3/8 1/8
Tube Outside Diameter (Large End) 3/8 in
Tube Outside Diameter (Small End) 1/8 in
Weight .005 lb

Other sizes

Parts that share this base number, ordered by size. Always verify the full specification before substituting.

Cross-reference

Interchangeable

Parts that share a National Stock Number or are listed as an alternate for AN919-4D — functionally equivalent.

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Catalog data updated 2026-07-05. Report a data error