Glock magazine extensions, baseplates and springs

A Glock magazine is four parts: a body, a spring, a follower and a floorplate with an insert. Changing the floorplate is the most common magazine upgrade, because it can add rounds, add grip length or both, and it takes a minute with no tools. This guide covers the types of baseplate and extension, the springs and followers that go with them, what fits which magazine, and the state rules that decide whether an extension is legal.

Factory floorplates and inserts

The factory floorplate is polymer, retained by a small insert that locks through a hole in the plate. Glock's own extended plates are the plus-two for the 26 and 27 subcompacts, which brings a 26 to 12 rounds, and the taller plate on the 19X and 45 magazines that makes a 17 body hold 19. The Gen 5 floorplate has a front lip to help rip a stuck magazine from the flared well. Factory plates fit factory magazines; aftermarket plates fit factory and Magpul bodies and say which.

Aftermarket baseplates

Aftermarket baseplates come in aluminum and polymer and in plus-zero, plus-one, plus-two, plus-four, plus-five and plus-six. A plus-zero replaces the factory plate with a flat aluminum one that is easier to strip from the pistol and harder to break; it adds no rounds. A plus-two on a 19 magazine gives 17 rounds and a small extension that the pinky can use. A plus-five on a 17 magazine gives 22 rounds and adds roughly an inch and a half of length, which is a range and competition setup. Every plate above plus-zero comes with a longer spring or requires one; using the factory spring under a plus-five leaves the last rounds weak. Aluminum is heavier and survives concrete; polymer is lighter and cheaper.

Pinky extensions

A pinky extension adds grip length without adding rounds. On a Glock 26 or 43, where the pinky hangs below the factory floorplate, an extension gives the whole hand a place and makes the pistol easier to control. Pinky extensions are legal in every state because they change nothing about capacity. They also make the pistol slightly harder to conceal, which is the trade.

Slimline: 43, 43X and 48

The 43 takes plus-one and plus-two floorplates that bring it to 7 or 8 rounds. The 43X and 48 share a 10-round magazine that takes plus-two plates, and the aftermarket also offers steel-bodied 15-round magazines for these two pistols; steel magazines need a steel magazine catch, sold with them, because the factory polymer catch wears against steel. The 15-round steel magazines have a mixed record and are best proven in your pistol before you carry them.

Springs

Magazine springs wear from cycling, not from sitting loaded. Replace them when the last round nose-dives, the slide stops locking back on empty or the follower tilts. Extra-power springs, usually ten percent stiffer than factory, help magazines that see a lot of dust or extended baseplates and cost a little more effort to load. Extended baseplates ship with the matching spring; pinky extensions and plus-zero plates use the factory spring. Keep a set of spare springs for carry magazines and replace them on a schedule, roughly every few thousand rounds or several years of use.

Followers

Glock followers are numbered by caliber and revision, and the Gen 5 9mm follower is orange so an empty magazine is obvious. Aftermarket followers in bright colors do the same job on older magazines. A cracked or worn follower tilts and causes the last-round failures that get blamed on springs; inspect it when you change the spring. Followers are cheap and take seconds to swap.

Magazine wells and floorplates

A flared magazine well on the pistol may need a compatible floorplate: some Gen 3 and Gen 4 magwells require an extended plate to lock the magazine in, and some competition magwells sit low enough that the factory plate catches. Check the magwell maker's fit list. Gen 5 magazines with the lipped floorplate work with the factory flare and most aftermarket wells.

Fitting a baseplate

Push the floorplate insert through its hole with a punch or the tip of a cartridge, slide the factory plate forward off the body while holding the spring down with a thumb, and let the spring and follower out slowly. Fit the new spring and follower, compress them with the new insert, slide the new plate on until it clicks, and confirm the insert is locked. Load the magazine to capacity, seat it in the pistol with the slide closed, and run a magazine at the range. A plate that will not seat on a closed slide is overfilled by one round or has the wrong spring.

Legality

Extended baseplates count toward state capacity limits. A plus-two on a 15-round magazine in a 15-round state is over the limit, and in a 10-round state any plate that raises a restricted magazine above ten is illegal. Plus-zero plates and pinky extensions are legal everywhere. We ship extended plates only where legal; the checkout tells you before payment. See magazine capacity laws by state and the fit rules in the compatibility chart.

What to buy

• Carry 19 or 43X: a pinky extension or a plus-zero aluminum plate, factory spring.
• Nightstand 17: factory plate; the 17 rounds are enough.
• Range and competition: plus-five aluminum plates with the included springs, where legal.
• Subcompact 26: factory plus-two or an aftermarket plus-two with a sleeve.

Browse baseplates and extensions and magazine springs, and keep them running with magazine care.

General information, not legal advice. Current as of September 2026. Laws change; check the official source before you act.