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AN8-43A
Aeronautical Standard Machine Bolt
Description
Hex head aircraft bolts are made of high-strength type 4037 or 8740 alloy steel (type 8740 is most commonly used). The bolts are centerless ground and threaded after heat treatment. Minimum tensile strength 125,000 PSI. Cadmium plated per specification QQ-P-416A, Type II, Class 3. Available with shank drilled for cotter pin or undrilled for stop nut application, and with or without drilled head for safety wire. Specify bolts to have undrilled shank by adding letter "A" after the dash number. For bolts with drilled head add letter "H" after the AN number. See illustrated examples. "C" represents Type 431 Stainless Steel (contains iron which is magnetic). The length of AN aircraft bolts is measured from under the head to the end of the shank. The "grip" is the unthreaded portion of the shank. See table for conversion of length and/or grip to proper AN callout. Note: Drilled bolts listed above are drilled shank only. To order drilled head only or both drilled head and shank bolts, please use our AN Bolt Selector by clicking the link below
Specifications
| Fastener Length | Between 4.453 inches and 4.500 inches |
|---|---|
| Features Provided | Finished head |
| Grip Length | 3 11/16, Between 3.672 inches and 3.703 inches |
| Hardness Rating | 26.0 rockwell c and 32.0 rockwell c |
| Head Height | Between 0.265 inches and 0.297 inches |
| Head Style | Hexagon Head |
| 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 military specification 6th material response |
| Min. Tensile Strength (psi) | 125000 pounds per square inch |
| Nominal Length | 4 15/32 |
| Surface Treatment | Cadmium and chromate |
| Surface Treatment Specification | Cl 3 federal specification all treatment responses type 2 qq-p-416 |
| Thread Class | 3a |
| Thread Diameter | 0.500 |
| Thread Direction | Right-hand |
| Thread Length | Between 0.750 inches and 0.828 inches |
| Thread Qty | 20 |
| Thread Qty Per Inch (tpi) | 20 |
| Thread Series | UNF |
| Thread Series Designator | Unf (fine thread) |
| Thread Size | 1/2 |
| Width Between Flats | Between 0.740 inches and 0.752 inches |
Cross-reference
No interchangeable or dimensionally similar parts are on record for AN8-43A. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error