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AN818-4J
Aeronautical Standard Tube Coupling Nut
Description
Coupling Nut
Specifications
| Connection Type | Flared Tube |
|---|---|
| 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 | CRES |
| NIIN | 00-203-2658 |
| NSN | 4730-00-203-2658 |
| Size No. Alum | 4D |
| Size No. SS | 4J |
| Size No. Steel | 4 |
| Thread Size | 7/16-20 |
| Thread T (MIL-S-8879) | 0.4375-20 |
| Tube O.D. | 1/4 |
| Tube Outside Diameter | 0.250 in |
| Weight | 0.025 lb |
Cross-reference
Interchangeable
Parts that share a National Stock Number or are listed as an alternate for AN818-4J — functionally equivalent.
- AN818-4 Same NSN 7/16-20 · Steel
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Catalog data updated 2026-07-05. Report a data error