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AN818-4D

AN Fitting AN818-4D Nut

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Description

Coupling Nut

Specifications

Connection Type Flared Tube
Criticality Code Justification Feat
Diameter A 0.305 in
Diameter C 0.562 in
Dimension A Tolerance +0.003 in
Dimension C Tolerance +0.000 in
Dimension J 0.400 in
Dimension M 0.620 in
Dimension M Tolerance +0.005 in
Dimension O 0.563 in
Dimension O Tolerance -0.004 in
Industry Standards/Certification AN818
Material Aluminum
Nut Height 0.620
Nut Style Tube coupling
Size No. Alum 4D
Size No. SS 4J
Size No. Steel 4
Special Features Weapon system essential. grumman a-10 aircraft
Surface Treatment Anodize
Thread Class 3b
Thread Direction Right-hand
Thread Qty Per Inch (tpi) 20
Thread Series UNF
Thread Size 0.438, 7/16-20
Thread T (MIL-S-8879) 0.4375-20
Tube O.D. 1/4
Tube Outside Diameter 0.250 in
Weight 0.01 lb
Width Across Flats 0.563

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