MTX 365 +3 Round Magazine Extender with Spring for P365

SKU: XTT132-BLK P365 Category: Tags: , ,


  • Works with Factory 10 Round Mag for standard P365 frame & Wilson Combat P365 Standard Frame
  • Includes Easy Loading Follower
  • Not for use with 12rd or 15rd mags; or P365x, P365xl, or P365 Macro frames.
  • Sig P365 Magazine Extension is Made in USA
  • Innovative Patented Design For 100% reliable function
  • The Grip Extension Provides Much Improved Grip and Control without going to the XL frame.
  • Custom Engineered Spring
  • Another benefit of the P365 finger extension, is that it provides the perfect pinky extension for tactile feel and control.
  • One of the Best P365 Upgrades
  • Detailed Installation Video QR Code
  • Patents: US 11,408,697 B2, US 11,168,954 B1


Our MTX 365 +3 gives you a much improved grip for your Sig Sauer P365 micro compact pistol. Not only will you find our MTX 365 to be a huge improvement over the Sig Sauer factory magazines, you will find this extension kit to be superior to the larger X / XL grip modules.

The ultimate upgrade for your Sig Sauer P365 pistol – the MTX 365 Plus, 3-Round SIG P365 Mag Extension! Transform your standard P365 into the extended grip length of the P365X/XL without compromising style or functionality by swapping the magazine. Made in the USA, this innovative and patented magazine extension is 100% reliable and designed to give you total control and improved grip on your firearm.

The SIG P365 Mag Extension is compatible with factory 10-round magazines for the standard P365 and Wilson Combat P365 frames. Please note that it is not intended for use with 12rd or 15rd magazines or P365X, P365XL, or P365 Macro frames. Our unique design enables the extender to work on the Sig mag body with inward-facing tabs where other extenders cannot be used. This also allows for seamless integration with the P365 platform without compromising the overall aesthetics of your firearm.

One of the main features of the SIG P365 Mag Extension is the custom-engineered spring, which guarantees unmatched reliability and ensures last-round bolt hold open. The MTX 365 +3 Round Magazine Extender also comes with a detailed installation video QR code to guide you through the simple process of adding this essential P365 upgrade to your firearm.

Furthermore, the SIG P365 Mag Extension provides the perfect pinky extension for tactile feel and control, allowing you to maintain accuracy and precision while shooting. In addition, the grip extension dramatically improves grip and control without having to go for the XL frame, giving you the confidence to manage your firearm in any situation successfully.

Lauded as one of the best P365 upgrades available on the market today, the MTX 365 +3 Round Magazine Extender with Spring for P365 takes your shooting experience to a whole new level. With its innovative, patented design, US 11,408,697 B2 and US 11,168,954 B1, and unparalleled reliability, this superior accessory is a must-have for any Sig Sauer P365 owner looking to enhance their firearm’s performance and take their shooting skills to new heights.


6 reviews for MTX 365 +3 Round Magazine Extender with Spring for P365

  1. William Murray (verified owner)

    Definitely one of the better polymer 365 extensions.

  2. Joseph Foss, Sr. (verified owner)

    Excellent craftsmanship! Installation takes seconds, excellent fit and finish.

  3. Jason (verified owner)

    Converted my 10-round magazines to get more use out of them. On installation one of the new spring sets did not set just right and the magazine would not load 13 rounds. Unloaded, disassembled, checked, and reassembled the magazine and it now loads 13 rounds properly. Overall a good product. I will update you when I have a few hundred rounds through these magazines.

  4. gmpevy (verified owner)

    5 stars. Converted my 10 round factory mags. Much cheaper than buying the larger sig mag. Take your time when making the conversion. Paper instructions are not the best. Watch the YouTube video. The first one took some time and frustration took over. After getting the first mag figured out and done, the second mag didn’t take more than three minutes. Quality product. Makes a huge difference in my grip on the pistol. I highly recommend XTech Tactical and this product

  5. Sam P (verified owner)

    Very nice product. I installed the +3 extender on one of my 10-round mags for use at the range. The fit and finish are excellent. I did use a pair of pliers to squeeze the extender into the mag, as suggested. That worked very well. Now I really like the feel of the extended grip. There was no problem loading rounds into the mag afterward. As is my standard practice, I used silicone spray in the mag and then wiped it before installing the spring.

  6. brandenlambeth (verified owner)

    After installing the 3+ magazine extension I ran a couple through the 365. I liked the new feel of the grip so much I ordered 2 more. I highly recommend this product.

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In 2013, XTech Tactical was formed to develop revolutionary firearms accessories for the AR style rifles and other small arms. Our products include AR15 Grips, AR15 Lower Parts Kit, and much more.

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