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AN4-25A
Aeronautical Standard Machine Bolt
Description
Airframe Bolt
Specifications
| Alternate Part Number | 400-018 |
|---|---|
| Country of Origin | USA |
| Drilling | Undrilled Head |
| Fastener Length | Between 2.641 inches and 2.688 inches |
| Features Provided | Finished head |
| Grip | 2 3/16 in |
| Grip Length | 2 3/16, Between 2.172 inches and 2.203 inches |
| Hardness Rating | 26.0 rockwell c and 32.0 rockwell c |
| Head Height | Between 0.140 inches and 0.172 inches |
| Head Style | Hexagon Head |
| Head Type | Hexagon |
| Industry Standards/Certification | AN4 |
| Length | 2 21/32 in |
| Material | Steel |
| Material Specification | Mil-s-5626 military specification 1st material response or mil-s-6049 military specification 2nd material response or mil-s-6050 military specification 3rd material response or mil-s-6098 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 | 00-151-1411 |
| NSN | 5306-00-151-1411 |
| Nominal Length | 2 21/32 |
| Surface Treatment | Cadmium and chromate |
| Surface Treatment Specification | Class 3 federal specification all treatment responses type 2 qq-p-416 |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | Between 0.438 inches and 0.516 inches |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series | UNF |
| Thread Series Designator | Unf (fine thread) |
| Thread Size | 1/4-28 |
| Weight | 0.042 lb |
| Width Between Flats | Between 0.428 inches and 0.440 inches |
Cross-reference
No interchangeable or dimensionally similar parts are on record for AN4-25A. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error