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Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube Up to $6.00 Off — 2 models

Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube, CASTLE
Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube, 24K Gold Plated, CASTLE-GP
Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube, CASTLE
1 of 2 images
Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube, CASTLE
Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube, 24K Gold Plated, CASTLE-GP
2 of 2 images
Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube, 24K Gold Plated, CASTLE-GP

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Questions & Answers
Customer Reviews
Most Recent Reviews
ordered silver. black showed up by ChiroShooter, Verified Owner, May 28, 2021
Wrong color. I specifically hunted down a silver colored castle nut one to have a black/blued finish castle nut arrive. It took me several weeks to find a silver castle nut in stock. Very disappointed
Most Recent Reviews
Nice castle nut by C-H-A-East, July 26, 2018
I received a castle nut from a friend and it had burrs. I definitely needed a replacement. I compared several on the site and ordered two different. This one worked perfectly for my needs. It matches what I have nicely, too.
Most Recent Reviews
Cast!e Nut by Patriot, May 27, 2018
Bought this to use with the SBA3 pistol brace that I installed on my AR pistol build. Quality manufacturing of the castle nut made it a breeze to install. There are no sharp edges. Precision cut threads help to prevent galling. Plan on purchasing ano...
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Read All 3 Reviews

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Product Info for Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube

Steel Fits Mil-spec/Commercial Buffer Tubesimage

Specifications for Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube:

Manufacturer: Guntec USA
Gun Model: AR-15

Features of Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube

  • Fits Mil-spec/Commercial Buffer Tubes

Package Contents:

  • Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube

What firearm models does the manufacturer say Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube is compatible with?

The manufacturer suggests that Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube is compatible with AR-15

Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube Orderable Models

List of Orderable Models

  • Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube, CASTLE , MPN: CASTLE , UPC: 714569643782 , Code: 2AH-CAN-CASTLE
  • Guntec USA AR-15 Castle Nut For Car/M4 Buffer Tube, 24K Gold Plated, CASTLE-GP , MPN: CASTLE-GP , UPC: 752574669984 , Code: 2AH-CAN-CASTLE-CASTLE-GP
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Last updated 2026-08-21 UTC.