Shield Mag Extension +5/4 for Glock 19/23 - Gray

The Shield Arms Magazine Extension +5/4 for Glock 19/23 is a compact capacity booster that gives your everyday carry or duty mag the extra rounds you might need without switching platforms. Add 5 rounds to a Glock 19 magazine or 4 rounds to a Glock 23 mag—a meaningful boost for 9mm or .40 S&W shooters who want more firepower in the same grip frame. Machined from 6061 aluminum and Type 2 anodized for durability, this gray extension sits flush with most aftermarket flared mag wells and keeps your gun running true.

What sets Shield Arms apart is the engineering. The unique floor plate design lets you access the spring and follower without removing the extension itself—no more wrestling with your magazine to perform basic maintenance or swaps. Index cuts on the body keep everything aligned, and the extension ships with an enhanced power spring tuned for reliable feeding under the added load. If you're building a reliable Glock setup or topping off your carry mag, this is a clean, American-made solution.

Shield Arms backs this extension with a lifetime warranty and their Spring for Life guarantee, so you're covered if anything goes wrong. Note that this extension is designed for OEM Glock 13 and 15 round magazines—verify your mag generation before ordering to ensure proper fit.

Key Features

• Adds 5 rounds to Glock 19 mags or 4 rounds to Glock 23 mags
• Quick-access floor plate design for fast spring and follower service
• Index cuts keep the extension securely positioned
• Machined 6061 aluminum with Type 2 anodize finish
• Fits most aftermarket flared mag wells
• Includes enhanced power spring rated for added capacity
• Made in the USA
• Lifetime warranty and Shield Arms Spring for Life guarantee

Specifications

Frequently Asked Questions

Will this Shield mag extension fit my Glock 19 or Glock 23?

Yes—this extension is designed for both platforms. It adds 5 rounds to Glock 19 magazines and 4 rounds to Glock 23 magazines. Make sure your mag is an OEM Glock 13 or 15 round magazine, as the extension is engineered for those generations.

Does this work with my mag well?

The extension is engineered to fit most aftermarket flared mag wells. If you're running an older or non-standard mag well, confirm fit before installing.

What comes in the box?

The package includes the extension body and an enhanced power spring tuned to handle the extra rounds. The unique floor plate design means you can service the spring without removing the extension from the magazine body.

Is the Shield mag extension backed by a warranty?

Yes. Shield Arms covers this extension with a lifetime warranty and includes their Spring for Life guarantee, so you're protected against defects for as long as you own it.