Aircraft Grade bolts - 1/4inch AN4

Check out our wide range of 1/4" Aircraft Grade Bolts engineered for the most demanding environments. Designed with high precision, these bolts feature a tight tolerance 1/4inch shank width, ensuring precise fits in critical applications such as suspension and chassis components.

Our Aircraft bolt range is imperial, not metric, due to the quantity of components on racing cars and aviation components that abide by that system and use compatible imperial components.

Our AN4 range of bolts refers to the thickness of the bolt, being 1/4 inch. All of our AN4 bolts have a 1/4 UNF thread.

We have an enormous stock inventory of bolt lengths for your application, each size is listed at the bottom of the page for reference. Keep in mind that the thread length on all bolts remains consistent, and the increase in under-head length is achieved with a longer shoulder (grip length). In shear applications where a bolt may need a longer shoulder (grip length) but packaging doesn't allow for the nut to tighten all the way to clamping, just pack a secondary washer under the head of the nut or bolt (this is common practice when using these bolts). 

With an impressive tensile strength of 125,000psi and shear strength of 76,000psi, these bolts will handle far more than you would initially expect. One of the key reasons we will always use a high quality AN bolt over any other is their metallurgic flexibility – designed to bend instead of shearing, offering another layer of safety in high-load applications, and might give you a chance of finishing a race with a bent bolt after a collision.

Each AN bolt is plated for corrosion protection and to prevent galling.

Tailored for aerospace and military applications, they boast a 6-point hex head and a flattened and precise washer mating surface. 

Our Aircraft grade bolts really are the ultimate choice for racing cars and high-level industrial applications. Find your correct length below and then add to cart via the top of the page.
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Please note sizes are in inches.

 Size Underhead overall length (shoulder and thread)
-3 0.5784"
-4 0.5784"
-5 0.7034"
-6 0.7815"
-7 0.9065"
-10 1.0315"
-11 1.1565"
-12 1.2815"
-13 1.4065"
-14 1.5315"
-15 1.6565"
-16 1.7815"
-17 1.9065"
-20 2.0315"
-21 2.1565"
-22 2.2815"
-23 2.4065"
-24 2.5315"
-25 2.6565"
-26 2.7815"
-27 2.9065"
-30 3.0315"
-31 3.1565"
-32 3.2815"
-33 3.4065"
-34 3.5315"
-37 3.9065"


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