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AN177-26
Aeronautical Standard Close Tolerance Bolt
Description
Close Tolerance Bolt
Specifications
| Country of Origin | USA |
|---|---|
| Distance From Head Largest Bearing Surface To Shank Hole Center | 2.672 inches nominal first hole |
| Fastener Length | 2.828 inches minimum and 2.875 inches maximum |
| Grip | 2 3/16 in |
| Grip Diameter | 0.4362 inches minimum and 0.4367 inches maximum |
| Grip Length | 2.172 inches minimum and 2.202 inches maximum |
| Hardness Rating | 26.0 rockwell c minimum and 40.0 rockwell c maximum |
| Head Height | 0.234 inches minimum and 0.266 inches maximum |
| Head Style | Hexagon Head |
| Head Type | Hexagon |
| Industry Standards/Certification | AN177 |
| Length | 2 13/16 in, 2 7/8 |
| Material | Steel |
| Material Specification | Mil-s-6049 mil spec 1st material response or mil-s-6098 mil spec 2nd material response or mil-s-5626 mil spec 3rd material response or mils-s-6758 mil spec 4th material response and mil-s-6050 mil spec 5th material response or ams 6300 assn std all material responses |
| Min. Tensile Strength (psi) | 125000 pounds per square inch |
| Shank Unthreaded Hole Diameter | 0.106 inches minimum first hole and 0.116 inches maximum first hole |
| Surface Finish | 63.0 microinches bearing surface of head, 63.0 microinches grip |
| Surface Treatment | Cadmium and chromate |
| Surface Treatment Specification | Qq-p-416 ty 2 cl 2 fed spec single treatment response |
| Thread Class | 3a |
| Thread Diameter | 0.438 |
| Thread Direction | Right-hand |
| Thread Length | 0.626 inches minimum and 0.703 inches maximum |
| Thread Qty | 20 |
| Thread Qty Per Inch (tpi) | 20 |
| Thread Series Designator | UNF |
| Thread Size | 7/16 |
| Weight | .15 lb |
| Width Between Flats | 0.615 inches minimum and 0.627 inches maximum |
Other sizes
Parts that share this base number, ordered by size. Always verify the full specification before substituting.
Cross-reference
No interchangeable or dimensionally similar parts are on record for AN177-26. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error