AR15 & AR9 Folding Stock Adapter Gen. 3

AR15 & AR9 Folding Stock Adapter Gen. 3


The Sylvan Arms Folding Stock Adapter allows you to fold your stock and significantly reduce the length of your rifle for easy stow and travel.

Specifically designed for gas piston and direct impingement systems .223 / 5.56 to .308 systems, it has standard 1-3/16” x 16 thread and does not require any additional parts to be used with standard Bolt Carrier Groups.

It is CNC-machined in the USA from 7075 Billet Aluminum, making it uniquely lightweight and corrosion resistant. This assembly weighs only 6.0 ounces. No special tools required; only a standard armorer’s wrench. The product does not need to be disassembled in order to install it on to your rifle/pistol.

Simply screw on, fold and carry!

Now Compatible with Silent Capture Buffer Springs! Click Here for our Silent Capture Bolt Extension!

Product Details

  • Includes standard .625 Bolt Extension
  • Fit: Platforms .223/5.56 to .308 & Most 9mm
  • 9mm bolt carriers with standard sizing, 5/8 ID (.625) can use the included bolt extension after removing the pin and weight from the back of the BCG
  • For smaller diameter BCG’s, we have 17/32 .531 bolt extensions available here
  • Now Compatible with Silent Capture Buffer Springs if you use our Silent Capture Bolt Extension
  • 300 blk (blackout) compatible
  • Adds 2 inches to length of pull
  • If your bolt carrier group is causing the bolt extension to come up short contact us for a conversion


  • Finish: Hard Coat Black Anodized
  • Material: 7075 CNC-machined billet Aluminum
  • Thread specifications: 1-3/16″ X 16
  • Hinge dimensions: 3 11/16 inches
  • Hinge Weight: 6.0 oz. Bolt Extension: 3.1 oz.
  • Hinge length: 1.3 inches
  • Warranty: limited lifetime

Designed, built and assembled in the USA

[Download Manual]

13 reviews for AR15 & AR9 Folding Stock Adapter Gen. 3

  1. Joe Limberg

    This folder is great but I had a problem with my buffer spring keeper pin. I had about 30 rounds through my BCM (which I’ve had thousands of rounds through) and it wouldn’t lock back on an empty mag. The keeper that comes in the folder broke. I tried replacing it with a standard keeper pin and I was to short which was disappointing. So I would recommend ordering extra keeper pins they are only $5. Other then that the product is solid and I really like it.

  2. Bob Guernon

    Excellent Product and easy to install and use. Wish I knew about this product sooner. Very solid lockup and easy to fold for easy storace in back pack.

  3. William Buck

    Ordered mine through Preppers back before they sold out of EVERYTHING, crazy times now though. Can’t compare to the LT unit but this is a tough well made unit and after a year or so on my 300 BLK pistol is still going strong except that the stock no longer stays folded, the aluminum is grooved where the detent ball bearings catch on the lip to hold it folded, it’s a total Who Cares on my part and doesn’t detract from the usability as IMHO you shouldn’t sling it folded since it can’t be fired when folded and I only fold it when stowed. One of the best aftermarket parts I’ve purchased. Great bang for the buck and easy peasy install, highly recommended!

  4. Aaron Cooper

    I’ve installed two Sylvan folding stocks. One on an AR9 and one on an AR-15. Both pistols and both function flawlessly. Very simple to install. No issues with operation and they are nice to look at. Overall, it’s a great product that functions and looks great and the company provides top notch customer support.

  5. Amos Ferguson

    I have 2 one on a foxtrot Mike ar9 5inch and one on a colt/poverty pony ar-15 and on both flawlessly installed and run great. I also must say the prices on replacement parts is great . I ordered extras of everything and it was 18.00 bucks ! I may never need them but now I have them and it wasn’t another 100 buckaroos. To have a just in case kit.

  6. Josh

    I own two and love them! Sylvan’s customer service is second to none. Alex was a huge help!

  7. Alex Leach

    Customer Service was great. I lost a spring retaining screw when taking this apart. 100% on me. I called on a holiday and there was no answer so I left a message. Less than 5 min later I got a call back and the person on the other line knew what I was talking about and helped me out right away saying they would send me a new one at no charge. Entire process took less than 2 min.

    Reason I lost the screw; was taking apart to move from my AK pistol to my favorite AR pistol (ordered another for AK). On the AK I used it with a the SB tactical brace adapter (699618782912). Was a good fit and worked great, sticking out a little with extra threading. May have been able to cut down for flush fit but I did not cut it down. Looks great on AR. Heavy Duty, Would recommend.

  8. David Rivas

    Awesome addition to my rifle. easy to install and no impact on firing.

  9. Josh (verified owner)

    I ordered this to go on my AR pistol so I could fit it in a Vertyx Gamut pack. Fits perfect with this adapter.
    This was a 5 minute install with the right tools, that everyone who has an AR should have. Highly recommend, and the stickers they gave me were huge!

  10. Jason

    This works very well and feels very sturdy. I doesn’t sit flush like the LT does so some threads show but I’m still satisfied with it. IMO the action of folding, unfolding, and staying feels better than the LT. The price point is a lot more reasonable. IMO this is the better buy for sure.

  11. charleslorenzohicks (verified owner)

    Just as good as the law tactical.. Nowhere near the cost.. Works perfect on my CQB Aero Precision 300 Blackout. Able to easily fit into my Vertx backpack NOW with room for several high capacity Mags. Locking mechanism is strong.. very easy to deploy. Will definitely purchase again for my 223 / 556 custom build.

  12. Rosario

    Wanted a pack my ar pistol in my backpack but it would not fit, I searched and came across this and I am very pleased with this product. It locks in nice and it is very sturdy. Something to consider if a gen 4 is manufactured is an adjustable tension mechanism for when the stock/brace is folded. The stock/brace is pretty loose in the folded position and would have loved an option to make it a bit more sturdy so it would not easily swing back to the closed position.

    Overall: 5/5

    Recommend: Yes!

    Build: solid and very well finished

    Functionality: 99% perfect with the exception of the mentioned above

    Installation: fairly easy, armorers wrench needed.

  13. Ger Lo (verified owner)

    Here’s my honest review. I was comparing this with Law Tactical. Watched all YouTube reviews of both. I was on a budget building my AR15 Pistol. I decided to go with Sylvan Arms. Boy did I make the best decision. The adapter was sturdy and my arm rest stayed in place. The bolt extender fit perfectly. I shot 200 rounds of mixed grains without any hiccups. I hit 5″ clay tagets at 100 yards with my iron sights perfectly. I’m pretty sure Law Tactical is good too but I’m sold on Sylvan Arms. Cheaper in price and quality is pretty stout.

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