There is a hollow cavity at the base of the Glock grip, behind the magazine well. A grip plug fills it. That stops brass, grit and lint collecting inside the frame, and it smooths the funnel into the magwell slightly, which helps on a fumbled reload.
How fitment works
Fitment is driven by frame generation and frame size. Gen 4 and Gen 5 frames use interchangeable backstraps, which changes the cavity shape, so a Gen 1–3 plug will not seat. Large-frame guns (20, 21, 40, 41) take a different plug from the standard frames, and the subcompacts differ again.
Fitment chart
| Glock model & generation | Part | Notes |
|---|---|---|
| Glock 17 Gen 4 | View part | |
| Glock 17 Gen 5 | View part | |
| Glock 19 Gen 3 | View part | |
| Glock 19 Gen 4 | View part | |
| Glock 19X Gen 4 | View part | |
| Glock 19X Gen 5 | View part | |
| Glock 21 Gen 3 | View part | |
| Glock 21 Gen 4 | View part | |
| Glock 22 Gen 3 | View part | |
| Glock 22 Gen 4 | View part | |
| Glock 22 Gen 5 | View part | |
| Glock 23 Gen 3 | View part | |
| Glock 23 Gen 4 | View part | |
| Glock 23 Gen 5 | View part | |
| Glock 26 Gen 4 | View part | |
| Glock 26 Gen 5 | View part | |
| Glock 34 Gen 3 | View part | |
| Glock 34 Gen 4 | View part | |
| Glock 34 Gen 5 | View part | |
| Glock 42 All | View part | |
| Glock 42 Gen 3 | View part | |
| Glock 43 All | View part | |
| Glock 43X All | View part | |
| Glock 45 Gen 4 | View part | |
| Glock 48 All | View part |
Choosing and fitting
Some plugs double as a takedown tool for punching out pins, which is worth having if you strip your own pistol. Check the plug seats fully and does not interfere with magazine insertion — a proud plug will slow reloads, which is the opposite of the point.