Magazine, for STI 2011 140mm 40/10mm 20 Rds, with Competition Follower, by MBX

3 Reviews
MBX Extreme
40 SW
20 Rounds
IL; CA; CT; MD; VT; OR; Oregon; HI; Washington DC.; MA; NY; NJ; New York; CO; VT; California; Colorado
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  • Attention Oregon: Starting 12/01/2022 high-capacity magazines will no longer ship to your state.
  • MBX Complete Tubes were designed to be competition ready with exclusive features to meet the highest demands for today's shooters.
  • This is for competition use and will NOT lock back the slide.
  • Made from Heat Treated 410 Stainless for Ultimate Durability. 
  • Witness holes on rear of tube to indicate round count for all tubes.
  • Restrictions apply in some states.


Write A Review
  1. Quality

    Posted by Leo on Jun 15th 2023

    I ordered my magazines with the standard slide stop follower. And thought for $130 dollars these have to be as good as the Staccatos. I was wrong. The followers look 3D printed, they're rough and uneven finish prevents them from protruding properly to engage the slide stop. Once I sanded them smooth it still only partially engages. The feed lips will also need to be adjusted. The poor quality molding on the follower causes the spring to be off centered in the follower causing it to tip forward, I've had this issue in my 10mm magazines as well as my .45 mags. Stupid of me to by from them twice. I'll be purchasing STI components to hopefully get them working. Do yourself a favor, save some money and buy something of quality like Staccato. Unless you like working on your mags and spending twice the money

  2. Flawless

    Posted by Joe on Apr 3rd 2017

    Bought these with my STI Edge. Follow the directions and load them to capacity and let them set. They have been absolutely flawless.

  3. Must have

    Posted by Eddie on Mar 1st 2017

    These mbx magazines come ready to go! The base pads remove easily and they hold 20 rd of pure excitement! What's there not to like