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Packaged Items
SinglePack of 10
Dash No.Nominal


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.

15% discount on qty of 50-99
20% discount on qty of 100+

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.

Click here for the AN Bolt Selector

Reference Chart

Reference Chart


Standard Part

Bay A Verified Purchase


November 5, 2023

Steve J Verified Purchase


May 15, 2022

Leslie H Verified Purchase


April 19, 2022

Agra F Verified Purchase


September 30, 2021

Michael P Verified Purchase


June 29, 2021

Prop bolts for my airboat.

George F
April 13, 2021

Aircraft Spruce is always a constant, and reliable source for what I need. Products are always of good quality. Shipping, well, I’m sure Aircraft Spruce has little latitude in that area.

Charles M
February 22, 2021

Could not find product and Aircraft Spruce came to the rescue and the pricing was excellent.

January 27, 2021

Was able to pick the bolts I needed, showed up perfect!

Zac J
January 4, 2021

perfectly good

Guillermo G
December 21, 2020


Please note, Aircraft Spruce Canada's personnel are not certified aircraft mechanics and can only provide general support and ideas, which should not be relied upon or implemented in lieu of consulting an A&P or other qualified technician. Aircraft Spruce Canada assumes no responsibility or liability for any issue or problem which may arise from any repair, modification or other work done from this knowledge base. Any product eligibility information provided here is based on general application guides and we recommend always referring to your specific aircraft parts manual, the parts manufacturer or consulting with a qualified mechanic.

Q: What is the diameter tolerance on a 3/8-24 AN bolt?

The max is .374", and min .371"

Q: What is the dash number of AN bolts?

The dash number designates the size and completes the part number. Example part numbers would be AN5-4, AN5-5, AN5-6, etc.

Q: What are the quantities for price breaks and the standard package quantities? I know you'll send any quantity, but I'd order above the price breaks and in multiples of the package quantities if they were listed.

The discount schedule for large quantities are: 50-100 = 15% / 100+ = 20%. Package quantities are usually 25 but we can sort them however you prefer as long as you mention it in special instructions at checkout.

Q: What is the safety wire diameter recommended for the drilled version?

It depends on the application, but both .032 and .041 will fit through the hole.

Q: On a drilled shank, where is the hole located in reference to the end?

Per the Tech Data Sheet, the hole location is determined from the start of the threads, on the head side, to the center of the drilled hole. AN3 = 17/64", AN4 = 5/16", AN5 = 23/64", AN6 = 7/16", AN7 = 31/64", AN8 = 39/64".

Q: What is the difference between stainless and cadmium plated AN bolts?

Stainless bolts are corrosion resistant for applications where corrosion is a problem. CAD plated bolts are made of steel with CAD plating to help surface corrosion, but it can been worn or chipped off.

Q: Is the nominal length listed the entire bolt (head, grip and thread) or just the grip and thread?

The nominal length is the length from under the head to the end of the shank.

Q: Picture clearly shows a bolt with both head drilled and shank drilled, but bolt selector does not allow that choice?

We do offer all of the types shown, but unfortunately not in every size. For example, drilled head is not available in AN4-3 stainless, but is available in AN5-4 cadmium.

Q: For the drilled shank, what is diameter of the drilled hole on AN3?

It is drilled for 1/16" cotter pin so it will be slightly larger than 1/16".

Q: what is the diameter of an4 bolt?


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