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AN818-4
Steel 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 |
| End Application | Grumman a-10 acft |
| Industry Standards/Certification | AN818 |
| Material | Steel |
| NIIN | 00-203-2658 |
| NSN | 4730-00-203-2658 |
| Nut Height | 0.609 |
| Nut Style | Tube coupling |
| Size No. Alum | 4D |
| Size No. SS | 4J |
| Size No. Steel | 4 |
| Specification Data | 88044-an818 government standard |
| Surface Treatment | Cadmium |
| Thread Class | 3b |
| Thread Direction | Right-hand |
| Thread Qty | 20 |
| Thread Qty Per Inch (tpi) | 20 |
| Thread Series | Unjf (fine thread with external controlled root radius) |
| 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 | 0.025 lb |
| Width Across Flats | 0.593 |
Cross-reference
Interchangeable
Parts that share a National Stock Number or are listed as an alternate for AN818-4 — functionally equivalent.
- AN818-4J Same NSN 7/16 in · CRES
Looking for a specific part? Use the cross-reference lookup.
Catalog data updated 2026-07-05. Report a data error