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Midwest Industries Alpha Series M4 Beam Side Folder Up to $10.00 Off w/ Free Shipping — 2 models

Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
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Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
2 of 4 images
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
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Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF
4 of 4 images
Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF

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Questions & Answers
Is this compatible with all sb braces an AR stocks? It is 5-6 position adjustable? Manufacturer Answer

Yes, this will work with SB Tactical braces that normally fit a buffer tube

by Midwest Industries, Manufacturer, March 5, 2025
how many positions is it with adjustable stock? Can you answer this question?
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review
Liked it so much I bought two more by Patriot Citizen, Verified Owner, June 2, 2024
Very strong and robust 1913 stock adapter. You could set this up to fold to left or right. This comes in with a left side fold plus you could either put in a pistol brace or butt stock depending on the size of barrel (have to buy separately). I love ...
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1/1 found this helpful
Helpful Positive Review
Great Folding Stock by JoePa, Verified Owner, May 14, 2023
I have this mounted on a PSA Jakl along with a Magpul stock. In the extended position it is very solid. When folded it has a little wiggle but it holds itself closed until you want it open. There is a little play on the fit of the stock, but nothing ...
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2/3 found this helpful
Helpful Negative Review
Needs improvement by Ty, Verified Owner, March 5, 2025
Has a ton of wobble with my sba4 brace because it only makes contact and the top rounded part of the folder and the locking hole on the bottom. It'd be nice if it was a inch or two longer also. Only reason I gave it two stars is it heavy duty. You're...
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2/2 found this helpful
Most Recent Reviews
Really nice. by JSL, Verified Owner, March 9, 2026
Got this for a BRN180 build and am very happy with it. Most stocks/braces fit well. some are a bit loose. a little tape wrapped under the stock/brace fixes this, though that is slightly obnoxious too have too do. Overall I am very happy with it, and...
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Most Recent Reviews
DO NOT BUY is your serious about AK's or folding AR's by Adam, Verified Owner, May 9, 2025
I love Midwest industries and have been using their handguards for years, but the M4 Beam Side Folder is a huge FAIL! As soon as I opened the box, I said to myself this thing is WAY heavy! Then when I installed it. This thing is extremely hard to ope...
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1/3 found this helpful
Most Recent Reviews
Too much play for attached stock by Ryan Craw, Verified Owner, May 2, 2024
The only problem with this setup is the amount of slop there is with the stock or brace you put on it. I'm trying different brands of stocks and I might be able to layer some tape on the top of the adapter arm to snug things up, but thats the only th...
Read More...
2/3 found this helpful
Read All 10 Reviews
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made-in-usa-flag Made in USA

Help support American manufacturing! Marked models of this product have gone through rigorous review and been certified by the manufacturer as Made in the USA.

Product Info for Midwest Industries Alpha Series M4 Beam Side Folder

The Midwest Industries Alpha Series M4 Beam Side Folder was created to function as the ideal item for anybody in need of an exceptional option..image

Established working with some of the most strong and long lasting components in existence, these AK Stocks from Midwest Industries will provide you with something that will give a great deal of reliability.

Midwest Industries has been making top quality merchandise for a very long time, and the Midwest Industries Alpha Series M4 Beam Side Folder is their very own approach to demonstrating how much they care.

Here at OpticsPlanet, we make it our obligation to receive the most suitable solution for all your requirements, and exhibiting the Midwest Industries Alpha Series M4 Beam Side Folder is a thing that we're delighted to offer.

Specifications for Midwest Industries Alpha Series M4 Beam Side Folder:

Manufacturer: Midwest Industries
Color: Black
Weight: 11.6 oz
Fabric/Material: 4140 Steel
Length: 7 in
Length of Pull: 6.25 in
Country of Origin: USA
Barrel Profile: M4

Features of Midwest Industries Alpha Series M4 Beam Side Folder

  • Heavy-duty side-folding mechanism constructed from 4140 steel
  • Full-length locking lug for maximum strength
  • Solid positive lock up in both positions
  • Steel clamp with large surface engagement
  • Can be configured to right or left folding
  • Modular design can accommodate different stock attachments
  • 2 QD Sling attachments
  • Compatible with Milspec diameter stocks
  • Curved top to mitigate wobble from skeletonized beam
  • Adds 7.0in to overall firearm length
  • Adds 0.75in to the firearm in the folded position
  • Steel parts are mag phosphate finished
  • Lifetime warranty

Package Contents:

  • Midwest Industries Alpha Series M4 Beam Side Folder

Midwest Industries Alpha Series M4 Beam Side Folder Orderable Models

List of Orderable Models

  • DEMO, Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF , MPN: MI-ALPHA-M4BSF-DEMO , Code: MWI-3AK-ASM4BSF-MI-ALPHA-M4BSF-DEMO-OB-A
  • Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF , MPN: MI-ALPHA-M4BSF , UPC: 812102034278 , Code: MWI-3AK-ASM4BSF-MI-ALPHA-M4BSF

Midwest Industries Alpha Series M4 Beam Side Folder Unavailable & Discontinued Models

List of Unorderable Models

  • USED, Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF , MPN: MI-ALPHA-M4BSF-EDEMO , Code: MWI-3AK-ASM4BSF-MI-ALPHA-M4BSF-EDEMO-RE-C
  • USED, Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF , MPN: MI-ALPHA-M4BSF-EDEMO , Code: MWI-3AK-ASM4BSF-MI-ALPHA-M4BSF-EDEMO-IN-C
  • USED Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF, EDEMO3, Condition Parts Only/Salvage, Defective , MPN: MI-ALPHA-M4BSF-EDEMO3 , Code: MWI-3AK-ASM4BSF-MI-ALPHA-M4BSF-EDEMO-DF-F
  • USED, Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF , MPN: MI-ALPHA-M4BSF-EDEMO , Code: MWI-3AK-ASM4BSF-MI-ALPHA-M4BSF-EDEMO-RE-B
  • DEMO, Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF , MPN: MI-ALPHA-M4BSF-DEMO , Code: MWI-3AK-ASM4BSF-MI-ALPHA-M4BSF-DEMO
  • USED Midwest Industries Alpha Series M4 Beam Side Folder, Black, MI-ALPHA-M4BSF, EDEMO2, Used, Condition Like New , MPN: MI-ALPHA-M4BSF-EDEMO2 , Code: MWI-3AK-ASM4BSF-MI-ALPHA-M4BSF-EDEMO2
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Last updated 2026-07-16 UTC.