Warne's $54.99 Aluminum Extension Puts 20 Rounds in Glock 43X/48
Warne has launched a +5 Extension that takes Glock's 15-round steel magazine to 20 rounds for the Glock 43X and Glock 48, and it does so without a new magazine body. Announced October 16, 2026, the aluminum extension lists at an MSRP of $54.99. Warne builds it in the USA, backs it with a lifetime warranty, and sells it only for Glock's own 15-round steel magazines. The magazine itself is not included. Buyers in ten states and D.C. cannot receive it at all, and the rest of the country has its own rules to check first.
Key Details
The extension is precision-machined from aluminum and finished in black anodize. A locking mechanism clamps it to the magazine tube, so it does not wobble or walk out of position under a firing grip. Each unit ships with a new magazine spring. That spring supplies the extra length and tension needed to feed five more cartridges reliably.
- Model: Warne +5 Extension
- Compatible pistols: Glock 43X and Glock 48
- Compatible magazine: Glock 15-round steel magazine only
- Total capacity: 20 rounds
- MSRP: $54.99
- Made in: USA
- Warranty: Lifetime, from Warne
- Magazine included: No
Warne says the aluminum does more than add capacity. The added mass sits at the base of the magazine, which helps it drop free when empty and speeds up magazine changes. A finger groove on the extension improves grip. Warne Director of Operations Victor Ianciuc says the parts were designed to improve durability and ergonomics alongside capacity.
Restricted shipping: Warne will not ship the extension to California, Colorado, Connecticut, D.C., Hawaii, Maryland, Massachusetts, New Jersey, New York, Washington or Vermont.
Background
The Glock 43X and Glock 48 are slimline 9mm pistols that Glock introduced in 2023. The 43X uses a single-stack grip, and the 48 adds a longer slide and barrel. Both were built to carry thin and shoot well. Their factory magazine capacities sit well below 15, so a 20-round option is a real change in how the guns behave, not a small tweak.
Magazine capacity has been a legal fault line for two decades. California has limited magazines to 10 rounds since 2000, and the Ninth Circuit sitting en banc upheld that limit in 2025. New York and New Jersey also restrict magazine capacity. Colorado has capped magazines at 15 rounds since 2013, which means a 20-round setup falls outside its limit regardless of where the magazine was bought. These laws predate the Supreme Court's 2022 decision in New York State Rifle & Pistol Association v. Bruen, which tightened the historical test courts must apply to gun regulations.
Why It Matters for Gun Owners
Anyone who owns a Glock 43X or 48 and lives in a permissive state now has a legal path to 20 rounds. The extension works with Glock's existing 15-round steel magazines, so owners do not have to buy a new magazine body or switch platforms. For a concealed carrier, the extension is a range and home-defense option, not a daily carry necessity. Five extra rounds add bulk, and the grip gets longer. Test the magazine on your own pistol before you trust it with a defensive load.
The shipping restriction matters as much as the product. The extension cannot reach buyers in the listed states through Warne's normal channels. Owners in states with capacity limits, including California, New York and New Jersey, cannot legally use a 20-round magazine even if they acquire one out of state. Check your county and city ordinances as well, because some local rules are stricter than state law. Keep receipts and verify the magazine's status before you bring it home.
DownRange Analysis
Bruen asks whether a modern regulation fits within the nation's historical tradition of firearm regulation. Magazine limits are the hardest category to defend under that test, because courts have struggled to find a clear founding-era analogue for capacity caps. Litigation over magazine bans will keep moving through the circuits, and a Supreme Court case on the question is plausible within the next few years. Until then, the law in each state controls.
From a market standpoint, aftermarket capacity products have grown because owners want more out of guns they already own. A $54.99 extension that fits an existing magazine is a low-cost way to test the idea. Our advice is simple. If you live in a state that allows 20-round magazines, verify the legal status of your magazine, buy from a dealer that ships to your state, and run the extension at the range before you rely on it. If you live in a restricted state, leave this one on the shelf.
