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AN176-21A
Aeronautical Standard Close Tolerance Bolt
Description
Close Tolerance Bolt
Specifications
| Country of Origin | USA |
|---|---|
| Drilling | Undrilled Head |
| Fastener Length | Between 2.187 inches and 2.234 inches |
| Grip | 1 9/16 in |
| Grip Diameter | Between 0.3737 inches and 0.3742 inches |
| Grip Length | Between 1.546 inches and 1.578 inches |
| Hardness Rating | 26.0 rockwell c and 32.0 rockwell c |
| Head Height | Between 0.203 inches and 0.235 inches |
| Head Style | Hexagon Head |
| Head Type | Hexagon |
| Industry Standards/Certification | AN176 |
| Length | 2 13/64 in |
| Material | Steel |
| Material Specification | Mil-s-6049 military specification 1st material response or mil-s-6050 military specification 2nd material response or mil-s-6098 military specification 3rd material response or mil-s-5626 military specification 4th material response or mil-s-6758 military specification 5th material response or ams 6300 assn standard 6th material response |
| Min. Tensile Strength (psi) | 125000 pounds per square inch |
| NIIN | 00-582-9965 |
| NSN | 5306-00-582-9965 |
| Surface Finish | 63.0 microinches grip, 63.0 microinches surface of head |
| Surface Treatment | Cadmium and chromate |
| Surface Treatment Specification | Qq-p-416 type 2 cl 3 federal specification single treatment response |
| Thread Class | 3a |
| Thread Diameter | 0.375 |
| Thread Direction | Right-hand |
| Thread Length | Between 0.609 inches and 0.688 inches |
| Thread Qty | 24 |
| Thread Qty Per Inch (tpi) | 24 |
| Thread Series | UNF |
| Thread Series Designator | Unf (fine thread) |
| Thread Size | 0.3750-24, 3/8 |
| Weight | 0.08 lb |
| Width Between Flats | Between 0.553 inches and 0.565 inches |
Cross-reference
No interchangeable or dimensionally similar parts are on record for AN176-21A. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error