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Strike Industries Multi-Function End Plate and Anti-Rotation Castle Nut
$36.95 $34.95 Save $2.00
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Most Helpful Positive Review Excellent idea
Looked like a neat idea. Picked up one to try out on a build I wanted to swap a few tubes on. This was exactly what was called for. Easy to install, easy to swap tubes in and out. The little set screw was fiddly on the first installation, but has become easy to use after that. Already picked up a 2n...
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Most Helpful Negative Review Good idea but overengineered?
This seemed like a great idea until I got to installing it. The set screws are very fiddly, especially the one for the non-slip castle nut. It's very easy to cross thread it and if you get it in crooked and strip it the $35 back plate goes in the garbage. I'd rather throw a cheap, staked castle nut ...
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Parts on the ar15 I needed to upgrade

by Tim, Verified Owner from MS, United States Written on July 26, 2025
Great products from this company, so far everything I've ordered has done it's job, highly recommended
Would recommend: Yes
Was it helpful to you? Yes | No

excellent replacement for the original parts

by Mark Zackery, Verified Owner from MA, United States Written on January 25, 2025
Easy to use and does stay in place, no need to stake it anymore and now you can attach any sling you want to it. Had it on my AR10 and worked great, will likely get another one for my AR15.
Would recommend: Yes
Was it helpful to you? Yes | No

works wonders

by Robert, Verified Owner from CO, United States Written on January 3, 2025
This allows you to change out your rear takedown detent or spring with ease!
Would recommend: Yes
Was it helpful to you? Yes | No

designed by toddlers for toddlers

by Dave, Verified Owner from PA, United States Written on December 27, 2024
Going to make this review quick because I already wasted so much of my time with this useless thing. It comes with 2 small set screws one to hold the spring for rear take down pin and one to secure the castle nut. I bet 50 dollars you don’t own an Allen key small enough to install the one screw. I’m sure you have a small enough flat head for the other, but after 1 hour of looking for it you will want to pull your hair out and burn it. They really couldn’t throw the right Allen key in with it? I don’t know, common sense to me is WHY WOULDN’T YOU MAKE THE SAME EXACT SET SCREWS USE THE SAME ALLEN KEY OR SCREW DRIVER?¿if your looking for a ratcheting castle nut systems please go buy the PWS ratcheting castle nut. Your sanity will thank me later.
Pros:
  • little to none
Cons:
  • everything
Best Used for:
  • wasting 1 hour of your weekend
Would recommend: No
1 of 1 found the following review helpful.
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Great End Plate

by Guy, Verified Owner from NC, United States Written on December 24, 2024
This thing looks slick and works wonderfully. Solves the pesky spring issue when pushing the end plate into place. Would definitely recommend.
Would recommend: Yes
Was it helpful to you? Yes | No

Single point and castle nut

by Ariel, Verified Owner from GA, United States Written on July 7, 2024
Everything I buy from Optics planet is QueLity Well priced and Delivered intact and in excellent time
Would recommend: Yes
1 of 1 found the following review helpful.
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High Quality Part and Really Is A Noticeable Upgrade

by Lee, Verified Owner from FL, United States Written on January 19, 2024
I was impressed with the quality of this end plate and especially the castle nut. The finish on the castle nut is superb and the metal is hard enough that it didn't wear the anodizing off when torquing it down. Visually, is nice without having to stake the castle nut since it has the screw that fits in the notch of the castle nut to keep it from loosening. Also a very functional added plus that my single point sling now readily attaches to my AR pistol. I plan to purchase again for my next AR pistol build.
Pros:
  • durable
  • Quality Finish
  • reasonable cost
  • multifunctional
  • Visual appeal
  • No staking needed.
Cons:
  • none I experienced
Would recommend: Yes
Was it helpful to you? Yes | No

Could be great, but fails on two points...

by Your Savior, from NY, United States Written on January 17, 2024
The only problems are:

#1) The anti-rotation set screw needs to be a bit bigger in diameter.

#2) When applying the proper torque value (that is included in the box/bag, on the warning card), it NEVER properly lines up! It's so frustratingly trial-&-error, that I recommend you just Red Loctite the castle nut & torque it a little past recommended value (as I did), & pray it never comes loose when firing/operation.

Only buy this if you need both H&K sling loop + QD sling socket + regular sling loop compatibility. Strike should've just went w/ PWS's ratcheting system. As stated above, the castle nut's ribs never properly align in order for you to insert the screw in correctly. The screw will screw down, but it will be at an angle & not perfectly straight.

Look, I would love for the anti-rotation feature to work as intended, as it allows you to not stake & swap out buffer tubes or perform maintenance w/o the need of breaking your staking. But, they need to update this w/ a wider anti-rotation screw + include a 90 degree (L-bend) hex wrench in the box/bag - as they don't include any wrench whatsoever. So, good luck sifting through your toolkit for anything adequate & properly sized. Absolute nightmare attempting to apply hand torque when tightening the screw w/ a zero-degree (straight) hex driver bit, as the hex screwdriver's shank is too wide & the castle nut ribs interfere w/ the screwdriver shank!

Again, love the principle & idea + added tri-sling compat. (All of the reas...
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Pros:
  • easy dissasembly for cleaning
  • Multi-Sling type compatibility
  • Side swappable/Flip-Over
Cons:
  • Anti-Rotation screw/pin too small in diameter
  • Castle Nut never lines up w/ anti-rotation screw hole after proper torquing
Best Used for:
  • Multi-Sling compatibility
  • Swapping extension tubes & cleaning
Would recommend: Yes
Was it helpful to you? Yes | No

Solid Product

by Derek Taylor, Verified Owner from TX, United States Written on January 4, 2024
Nothing special or exciting here. Both parts function exactly as they should. The small screw will hold the spring in place and can be installed before or after placing the spring. The detent retention spring will come out the hole without the screw holding it in place.
Would recommend: Yes
Was it helpful to you? Yes | No

Be very careful.

by Bruce Hasson, Verified Owner from GA, United States Written on January 26, 2022
They are not joking when they say 35ft#, in fact on the second go round I'm going to 32. Yep you guessed it, snapped the castle nut. If you meet the torque spec,, do not try to go a little more to lign up the screw hole for thr anti rotate screw,, you better back up a notch,, which is not the correct method. Now the joy of waiting for a terrible carrier to get the product into the hands of a worse carrier. DHL is the second worst delivery service option only thing worse is USPS. OP is a decent vendor and have many of the trick products others may not have.
Pros:
  • Easy to install
  • Well thought out design
Cons:
  • Brittle
Would recommend: Yes
2 of 2 found the following review helpful.
Was it helpful to you? Yes | No
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