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AN4C27
Aeronautical Standard Bolt
Description
Fastener Length: 2-15/16", Thread: 1/4-28, Thread Length: 33/64"
Specifications
| Distance From Head Largest Bearing Surface To Shank Hole Center | 2.734 inches minimum first hole and 2.766 inches maximum first hole |
|---|---|
| Fastener Length | 2.891 inches minimum and 2.938 inches maximum |
| Features Provided | Finished head |
| Grip Length | 2.422 inches minimum and 2.453 inches maximum |
| Hardness Rating | 26.0 rockwell c minimum and 32.0 rockwell c maximum |
| Head Height | 0.140 inches minimum and 0.172 inches maximum |
| Head Style | Hexagon Head |
| Length | 2 15/16 |
| Material | Steel |
| Material Specification | Mil-s-18732 mil spec single material response |
| Min. Tensile Strength (psi) | 125000 pounds per square inch |
| Shank Unthreaded Hole Diameter | 0.076 inches minimum first hole and 0.086 inches maximum first hole |
| Surface Treatment | Passivate |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | 0.438 inches minimum and 0.516 inches maximum |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series Designator | UNF |
| Thread Size | 1/4 |
| Width Between Flats | 0.428 inches minimum and 0.440 inches maximum |
Cross-reference
Similar parts
Parts with matching key dimensions — often from a different standards family. Candidates for comparison only; verify the full specification before substituting.
- AN4C27A AN 1/4-28 · 0.086 in · Hexagon Head · Steel
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Catalog data updated 2026-07-05. Report a data error