AT3™ Castle Nut for AR-15 Buffer Tubes - 9 Colors Available
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🎁 Holiday & Black Friday Buyer’s Guide 2025
🎁 Holiday & Black Friday Buyer’s Guide 2025
Most in-stock items ship within 3–4 business days.
If an item shows Backorder or Special Order, extra vendor lead time applies.
To ensure delivery before Christmas, place your order by the following dates (includes fulfillment time):
USPS Ground Advantage – Order by Dec 13
USPS Priority Mail – Order by Dec 14
USPS Priority Mail Express – Order by Dec 16
UPS 3-Day Select – Order by Dec 15
UPS 2-Day Air – Order by Dec 18
UPS Next Day Air – Order by Dec 19
International customers: Order by Nov 28 – Dec 5, depending on service and location.
For full vendor lead times and detailed shipping info, read the complete Holiday Buyer’s Guide →
🚚 Shipping Information
🚚 Shipping Information
Most in-stock items ship within 3 business days.
Special order items are typically processed within 14 business days (excluding weekends and holidays).
Custom items may require additional time depending on production schedules.
If you’d like to receive your order sooner, please select an expedited shipping option at checkout.
Some products ship directly from the manufacturer, and an equivalent carrier or service level will be chosen to match your selected shipping speed.
Shipping delays caused by carriers are outside our control, but we’ll always help track updates.
See our Shipping Policy for details.
🔄 Returns & Warranty Support
🔄 Returns & Warranty Support
Returns are accepted within 14 days for items that are unused, unopened, and in original packaging with no damage.
A restocking fee applies, but it may be partially waived if store credit is selected instead of a refund to the original payment method.
Custom builds, sale items, and hazardous goods are final sale.
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 Customers
🌍 International Customers
We ship worldwide to Canada, Mexico, Europe, Asia, and Oceania, including:
🇨🇭 Switzerland • 🇨🇿 Czechia • 🇩🇪 Germany • 🇩🇰 Denmark • 🇪🇸 Spain • 🇫🇮 Finland • 🇫🇷 France • 🇬🇧 United Kingdom • 🇭🇰 Hong Kong SAR • 🇮🇪 Ireland • 🇮🇹 Italy • 🇯🇵 Japan • 🇰🇷 South Korea • 🇲🇾 Malaysia • 🇳🇱 Netherlands • 🇳🇴 Norway • 🇵🇱 Poland • 🇵🇹 Portugal • 🇸🇪 Sweden • 🇸🇬 Singapore • 🇦🇺 Australia • 🇳🇿 New Zealand • 🇦🇪 UAE and more.
Transit averages 2–4 weeks depending on customs clearance. We are not responsible for customs delays. Reduced transit times are only available through expedited shipping options.
Import duties, VAT, and taxes are not included in your order total and must be paid by the recipient.
If a package is rejected, unclaimed, or returned due to unpaid duties, an incorrect address, or failure to collect, it will be handled under our Refund Policy. Shipping costs are non-refundable in these cases.
Pressurized or restricted items ship ground only where permitted.
Questions? Contact ops@hrtacticalin.com before checkout.
🎖️ GovX Military, First Responder & Teacher Discount
🎖️ GovX Military, First Responder & Teacher Discount
Description
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
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