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Ar-15 Buffer Tube Lock Nut - Receiver Extension Lock Nut For Ar-15 Black
Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.
$8.99
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SKU: 100054357
Overview
This mil-spec receiver extension lock nut is intended for AR15 carbines equipped with an adjustable stock, making it a practical part for both new builds and replacement work. It serves as the castle nut used with the receiver extension, offering a straightforward option when assembling or refreshing a carbine setup. The black finish keeps the look subdued, and the part is made in the USA by Aero Precision. For hunters and shooters who want a simple, purpose-built component without unnecessary extras, it fits a focused build approach.
Why Hunters Choose the Aero Precision
Mil-spec Receiver
Extension lock nut for AR15
Suitable New
Builds or as a direct
Made Usa
Aero Precision
Manufactured product
Black Finish
Matches the listed product title
Key Features
- Mil-spec receiver extension lock nut for AR-15 carbines with an adjustable stock.
- Also called a castle nut for buffer tube applications.
- Suitable for a new build or as a direct replacement part.
- Black finish.
- Made in the USA.
- Manufactured by Aero Precision.
Best Used For
- AR-15 carbine builders needing a mil-spec receiver extension lock nut for an adjustable stock setup.
- Shooters replacing a worn castle nut during routine AR-15 carbine maintenance or repair.
- Users assembling a new AR-15 carbine and wanting a direct-fit receiver extension lock nut.
- Aero Precision customers looking for a black buffer tube lock nut for a compatible build.
Specifications
| Color | Black |
|---|---|
| Compatibility | AR15 carbines with an adjustable stock |
| Country Of Origin | USA |
| Made In Usa | Yes |
| Mil Spec | Yes |
| Product Type | Receiver extension lock nut (castle nut) |
Pros
- Mil-spec receiver extension lock nut for AR15 carbines with adjustable stocks.
- Suitable for new builds or as a direct replacement for worn parts.
- Made in the USA.
- Aero Precision manufactured product.
- Black finish matches the listed product title.
Considerations & Trade-offs
- Designed specifically as a mil-spec receiver extension lock nut for AR15 carbines with an adjustable stock, so it is not a universal part for every rifle setup.
- This is a replacement or build component rather than a complete stock assembly, so it addresses only one part of the buffer tube system.
- The product information does not include compatibility details beyond AR15 carbines with an adjustable stock, so fit should be verified against the intended build.
- At this price point, it is a small hardware item intended for a specific function, not a multi-purpose accessory.
Suggested Comparisons
- AR-15 receiver extension components
- AR-15 stock hardware
- AR-15 lower receiver parts
- AR-15 build accessories
Suggested Accessories
- Armorer's wrench
- Receiver extension
- Buffer tube
- Stock assembly
Frequently Asked Questions
What is this part used for on an AR-15 carbine?
It is a mil-spec receiver extension lock nut, also called a castle nut, for use on AR15 carbines with an adjustable stock.
Is this intended for a new build or replacement use?
Yes. The product description says it is suitable for a new build or as a direct replacement for worn out parts.
Does this fit all AR-15 setups?
The provided data only says it is for AR15 carbines with an adjustable stock. It does not specify compatibility beyond that.
Who makes this lock nut?
The manufacturer listed is Aero Precision.
Where is it made?
The description states that it is made in the USA.