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AN4DDH21A
Aeronautical Standard Machine Bolt
Description
Fastener Length: 2-5/32", Hole Diameter: 3/64", Thread: 1/4-28, Thread Length: 15/32
Specifications
| Fastener Length | 2.156 |
|---|---|
| Features Provided | Finished head |
| Grip Length | 1.688 |
| Head Height | Between 0.140 inches and 0.172 inches |
| Head Style | Hexagon Head |
| Hole Configuration Style | Hexagon flats |
| Hole Diameter | 0.046 |
| Hole Quantity | 1 |
| Hole Type | Drilled |
| Length | 2 1/8 |
| Material | Aluminum |
| Material Specification | Qq-a-267 federal specification 1st material response or qq-a-268 federal specification 1st material response or mil-w-7986 military specification 2nd material response |
| Min. Tensile Strength (psi) | 62000 pounds per square inch |
| Surface Treatment | Oxide film and anodize |
| Surface Treatment Specification | Mil-c-5541 military specification 1st treatment response and mil-a-8625 military specification 2nd treatment response |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | 0.468 |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series | UNF |
| Thread Series Designator | Unf (fine thread) |
| Thread Size | 1/4 |
| Width Between Flats | Between 0.428 inches and 0.440 inches |
Other sizes
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Catalog data updated 2026-07-05. Report a data error