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AT3 Tactical Castle Nut for AR-15 Buffer Tubes Up to 33% Off, Coupon Available — 6 models

AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Black, AT3-Castle-01
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, FDE, AT3-Castle-01-FDE
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Blue, AT3-Castle-01-BLU
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Red, AT3-Castle-01-RED
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, ODG, AT3-Castle-01-ODG
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Pink, AT3-Castle-01-PNK
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Black, AT3-Castle-01
1 of 6 images
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Black, AT3-Castle-01
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, FDE, AT3-Castle-01-FDE
2 of 6 images
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, FDE, AT3-Castle-01-FDE
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Blue, AT3-Castle-01-BLU
3 of 6 images
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Blue, AT3-Castle-01-BLU
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Red, AT3-Castle-01-RED
4 of 6 images
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Red, AT3-Castle-01-RED
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, ODG, AT3-Castle-01-ODG
5 of 6 images
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, ODG, AT3-Castle-01-ODG
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Pink, AT3-Castle-01-PNK
6 of 6 images
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Pink, AT3-Castle-01-PNK

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Questions & Answers
Is the cerakote a matte or shinier finish ? Expert Answer

The AT3 Tactical Castle Nut is offered in Black or 9 colored Cerakote finishes.

by Ethan, Gear Expert, December 8, 2022
Why aren’t these labeled as “Made in the USA”? Are they? Can you answer this question?
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review Perfect fit and finish at a great price by Koop, Verified Owner, November 17, 2023
This was a very close match to my Magpul FDE furniture. Very pleased with the quality of the coating. Went on and has stayed on with zero issues
1/1 found this helpful
Helpful Positive Review SHINNY Black by gospyro, Verified Owner, April 12, 2022
I got this for a build where I was wanting to match up the blacks. The ATC castle nut is very black, but was TOO shiny/glossy. So if you want a castle nut that is turely black AND shiny this would be for you.
4/8 found this helpful
Helpful Negative Review Not Shiny Black by Skippy, Verified Owner, May 15, 2023
I read the review, and expected a shiny, black castle nut. I received 3 dull, flat black castle nuts. These were on back order for over 3 months, and when they arrived, not even meet the description. They are steel, and work fine, but the color fo...
Read More...
4/8 found this helpful
Most Recent Reviews Castle Nut for AR-15 Buffer Tubes In Flat Red by fox, Verified Owner, May 16, 2025
Not certain if the color is painted or anodized or something else but it's nice just the same. Deliveries are long because a lot of items sold are not stocked, but I waited in order to finish my build.
Most Recent Reviews Red Castle Nit by fox, Verified Owner, May 8, 2025
Finishes off my 10mm nicely. Like the duller red finish on it too.
Most Recent Reviews AR castle nut for Casper by BMB, Verified Owner, March 21, 2025
Worked as it should. Easy to use. Good quality as I always expect from Optics Planet! You guys are the best!
Read All 34 Reviews
Eligible models will have a savings offer. Apply coupon and add the item to your cart for savings on that select model! Limited time only. Cannot be combined with other promotions or offers. See promotion details.
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Product Info for AT3 Tactical Castle Nut for AR-15 Buffer Tubes

This steel castle nut is an essential piece of an AR15 buffer tube/stock assembly. With standard cuts for use with armorers wrench, and smaller cuts for staking the castle nut and endplate for a secure hold, this part does everything it should at a good price. If youre in need of a spare for a new build or replacing a damaged component, this one is right for you. You can also add a little more color to your black rifle with with your choice of Cerakote finish.image

Specifications for AT3 Tactical Castle Nut for AR-15 Buffer Tubes:

Manufacturer: AT3 Tactical
Gun Model: AR-15
Condition: New
Fabric/Material: Steel

Features of AT3 Tactical Castle Nut for AR-15 Buffer Tubes

  • Finish: Black or colored Cerakote finishes
  • Thread: Mil-Spec
  • Compatible with armorers wrench

Package Contents:

  • AT3 Tactical Castle Nut for AR-15 Buffer Tubes

AT3 Tactical Castle Nut for AR-15 Buffer Tubes Orderable Models

List of Orderable Models

AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Black, AT3-Castle-01 , MPN: AT3-Castle-01 , UPC: 5060748421012 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, FDE, AT3-Castle-01-FDE , MPN: AT3-Castle-01-FDE , UPC: 5060748421029 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-FDE
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Blue, AT3-Castle-01-BLU , MPN: AT3-Castle-01-BLU , UPC: 5060748421067 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-BLU
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Red, AT3-Castle-01-RED , MPN: AT3-Castle-01-RED , UPC: 5060748421074 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-RED
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, ODG, AT3-Castle-01-ODG , MPN: AT3-Castle-01-ODG , UPC: 5060748421036 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-ODG
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Pink, AT3-Castle-01-PNK , MPN: AT3-Castle-01-PNK , UPC: 5060748421050 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-PNK

AT3 Tactical Castle Nut for AR-15 Buffer Tubes Unavailable & Discontinued Models

List of Unorderable Models

USED, AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Black, AT3-Castle-01 , MPN: AT3-Castle-01-EDEMO , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-EDEMO-IN-C
USED, AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Black, AT3-Castle-01 , MPN: AT3-Castle-01-EDEMO , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-EDEMO-RE-B
AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Grey, AT3-Castle-01-GRY , MPN: AT3-Castle-01-GRY , UPC: 5060748421043 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-GRY
USED AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Blue, AT3-Castle-01-BLU, EDEMO2, Used, Condition Like New , MPN: AT3-Castle-01-BLU-EDEMO2 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-BLU-EDEMO2
USED AT3 Tactical Castle Nut for AR-15 Buffer Tubes, Blue, AT3-Castle-01-BLU, EDEMO3, Used, Condition Fair , MPN: AT3-Castle-01-BLU-EDEMO3 , Code: 4U2-CAN-ATT1215-AT3-CASTLE-01-BLU-EDEMO3
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