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  • Colt M4/AR15 Receiver Extension Castle Nut

    • Colt M4/AR15 Receiver Extension Castle Nut

    Colt

    $9.95
    (34 reviews) Write a Review
    SKU:
    9390020
    Previous Part Numbers:
    64069
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    Product Description

    Factory Colt receiver extension castle nut for M4/AR15 type rifles.

    Product Videos

    Custom Field

    Previous Part Numbers 64069

    Product Reviews

    Write a Review

    34 Reviews Hide Reviews Show Reviews

    • 5
      A+

      Posted by jv on 11th May 2020

      A+

    • 5
      Great replacement

      Posted by Pedro Suarez on 5th May 2020

      If your building a new build or replacing an old existing part, look no further, this is what you need.

    • 5
      Colt castle nut

      Posted by Charles E. on 26th Aug 2019

      Quality part; fit and finish is perfect. Colt's has the notches for proper staking of the end plate. As always, great AU service!

    • 5
      Colt Receiver Extension Castle Nut

      Posted by Michael Wiseman on 2nd Apr 2019

      My Colt castle nut was shipped fast and is typical Colt quality. AU is my go to for Colt products.

    • 5
      Colt quality, great price

      Posted by Mark on 13th Mar 2019

      High quality mil-spec part. A.U. Great company.

    • 5
      First Purchase

      Posted by Randy Ciuros on 5th Jan 2019

      I needed an extra castle nut, preferably Colt brand, and Arms Unlimited had it at the best price, with free shipping to boot.

    • 5
      Colt Parts

      Posted by Thomas R Griffith on 25th Dec 2018

      Always top notch parts, AU always efficient with fast service.

    • 5
      Colt M4/AR15 Receiver Extension Castle Nut

      Posted by Marty on 19th Nov 2018

      AU sells authentic Colt parts and the Colt M4 Receiver Extension Castle nut is no exception. Castle nut was brand new. The exceptional things about AU are their customer service, best prices on Colt products, fast shipping and no tax!

    • 5
      More Colt parts.

      Posted by Eric McKeown on 10th Jul 2018

      Nice to be able to buy individual lower parts with free shipping.

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