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AT3 Tactical logoAT3 Tactical

AT3 Castle Nut for AR-15 Buffer Tubes

Firearm-compatible AR-15 castle nut with steel construction, Mil-Spec threading, staking notches, wrench cutouts, and multiple color options.

Rated 5 out of 5 based on 1 review5 out of 51 review
$5.99
Vendor
AT3 Tactical
Type
Buffer Tube
SKU
AT3-Castle-01
UPC
98720034
Weight
0.1 lb
Availability
In stock

Specifications

Platform Compatibility
Mil-Spec AR
Specifications
Platform Compatibility
Mil-Spec AR

Color

Quantity
1
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Serving Detroit, Eastpointe, Warren, Macomb County, Oakland County, and Metro Detroit.

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Description


Secure and Reliable Fit

Ensure rock-solid stability for your AR-15 buffer tube and stock assembly with this high-quality steel castle nut. Designed for precise fitment and durability, this MIL-SPEC castle nut features standard armorer’s wrench cutouts for easy installation, along with staking notches for added security. Whether you’re building a new rifle, upgrading components, or replacing a worn-out nut, this affordable and rugged castle nut is a must-have.


Key Features:

High-Strength Steel Construction – Provides maximum durability and long-lasting performance.
MIL-SPEC Threading – Ensures secure compatibility with standard AR-15 buffer tubes.
Staking Notches for Secure Installation – Prevents loosening over time, maintaining reliability in demanding conditions.
Compatible with Armorer’s Wrench – Allows for hassle-free installation and removal.
Multiple Cerakote™ Color Options – Add a custom touch to your rifle with FDE, OD Green, Pink, Red, Blue, Burnt Bronze, Tungsten, or Titanium.
Black Phosphate Finish Option – Classic, corrosion-resistant finish for a sleek and tactical look.
Perfect for AR-15 Builds & Upgrades – Works seamlessly with all MIL-SPEC AR-15 lower receivers and buffer tubes.


Available Finishes:

🎨 Customize your build with premium Cerakote™ finishes:

🔹 Black: Phosphate finish for a classic, durable look
🔹 Flat Dark Earth (FDE): H-267 Magpul® Flat Dark Earth
🔹 OD Green (ODG): H-232 Magpul® OD Green
🔹 Pink: H-224 SIG™ Pink
🔹 Red: H-167 USMC Red
🔹 Blue: H-171 NRA Blue
🔹 Burnt Bronze: H-148 Burnt Bronze
🔹 Tungsten: H-237 Tungsten
🔹 Titanium: H-170 Titanium


Built for AR-15 Enthusiasts & Professionals

🔸 Ideal for rifle builders, gunsmiths, and AR-15 enthusiasts
🔸 Designed for secure fitment on MIL-SPEC buffer tubes
🔸 Ensures long-term durability and enhanced performance

When reliability and stability matter, trust this steel castle nut to lock your buffer tube assembly in place.

Upgrade your AR-15 today with a battle-tested castle nut that won’t let you down!AT3

Customer Reviews