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Questions & Answers
Customer Reviews
Helpful Positive Review better than some by DARKWING, Verified Owner, February 11, 2018
I have several of these. This is just for stocking at this time. I mean it is a castle nut , not much can go wrong. However the threads and wrench slots are better than some. The color is even and match's my upper/lower.
3/3 found this helpful
Most Recent Reviews Castle nut by Virginian, Verified Owner, December 19, 2023
This is a milspec castle nut that has a durable coating and has remained tight since installation
Most Recent Reviews Good quality by Gsdduke, December 4, 2018
Castle nut fits nice and snug. Coding looks nice. Metal looks nice and sturdy. Overall very good quality. It fits on my mail spec tube. Strike Industries quality is top-notch. I would recommend this product.
Most Recent Reviews color is off. by Mars, Verified Owner, June 30, 2018
It’s a dark grey color. Doesn’t match any buffer tube I have, including some from SI. Otherwise it’s a castle nut. Works, but if you expect a rich black color, look somewhere else. Threads are ok. Machining looks fine.
Read All 4 Reviews

Product Discontinued by Manufacturer

Strike Industries SI-AR-15/M16 Receiver Extension Castle Nut has been discontinued by Strike Industries and is no longer available. Our product experts have helped us select these available replacements below.You can also explore other items in the Gun Parts, AR 15 Parts, Rifle Parts, AR15 Lower Parts yourself to try and find the perfect replacement for you!

Product Info for Strike Industries SI-AR-15/M16 Receiver Extension Castle Nut

Receiver Nut for collapsible receiver extension, also referred to as a Castle Nut. This Mil-Spec part with fit both the Mil-Spec and commercial receiver extensionsimage

Package Contents:

  • Strike Industries SI-AR-15/M16 Receiver Extension Castle Nut

Related Products to Strike Industries SI-AR-15/M16 Receiver Extension Castle Nut

Strike Industries SI-AR-15/M16 Receiver Extension Castle Nut Unavailable & Discontinued Models

List of Unorderable Models

Strike Industries SI-AR-15/M16 Receiver Extension Castle Nut, Black, SI-AR-RE7P-CN , MPN: SI-AR-RE7P-CN , UPC: 700598349702 , Code: 3Q-CAN-SIARM16RVECN-SI-AR-RE7P-CN
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