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AT3 Tactical

AT3 Castle Nut for AR-15 Buffer Tubes

Regular priceFrom $5.99 USD
Shipping calculated at checkout.

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

Color:

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⚠️ Sold for sporting and training applications. Customer is responsible for ensuring compliance with all applicable local laws and regulations. See Terms .


🚚 Shipping & Delivery

Most in-stock orders are typically processed within 1–2 business days before carrier handoff. Processing time is separate from carrier transit time.

The shipment estimate shown above appears only for eligible in-stock, inventory-tracked variants. Backordered, preorder, special-order, custom, imported, and manufacturer-direct items may take longer. Product-specific dates are provided in good faith and are not guaranteed delivery dates.

Available shipping services, final charges, and carrier transit estimates are shown at checkout. See our Shipping Policy for current details.

🔄 Returns, Exchanges & Warranty

Eligible non-custom returns must be requested within 30 days of delivery. Items must be unused, uninstalled, unmodified, and in their original, undamaged packaging.

Eligible standard returns may be subject to a 15% restocking fee. EU withdrawal returns are handled under applicable statutory rights; prohibited restocking fees do not apply, though lawful diminished-value deductions may.

Custom products, sale items, gift cards, perishable or personal-care goods, and hazardous materials are non-returnable except where applicable law or an approved warranty or defect claim requires otherwise.

Warranty Coverage: Manufacturer warranties apply to all standard products. Any defects, malfunctions, or performance issues are handled directly by the manufacturer per their terms.

HR Tactical Innovations covers a Fitment & Functionality Guarantee on all custom or modified items — if a verified production error occurs, we’ll replace the item.

View our Refund Policy for full details.

🌍 International Shipping

International shipping availability depends on the product, destination, applicable restrictions, and the services offered at checkout. Not every product can be shipped to every country or region.

Available services, charges, and any delivery estimates are calculated for the order and destination at checkout. Carrier and customs processing can affect delivery timing.

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Refused, unclaimed, returned, lost, seized, or delayed shipments and related claims are handled case by case under our current Shipping Policy, Refund Policy, and applicable law.

Questions? Contact [email protected] before checkout.

🎖️ Military / GovX Discounts

⚙️ Product Details

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

Specifications

  • Platform Compatibility
    Mil-Spec AR

Reviews & Questions (1)

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