ProMag GLKA21 9mm Luger 20-Rd Black Polymer Pistol Magazine for Glock 17/19/26

The ProMag GLKA21 is a 20-round extended-capacity 9mm Luger pistol magazine built specifically for the Glock 17, Glock 19, and Glock 26 (and other compatible 9mm Glock-pattern frames).

Featuring a black finish and a magazine body constructed of a proprietary DuPont Zytel based polymer, this detachable double-stack magazine offers Glock owners an affordable way to expand their magazine inventory for range training, competition, and high-volume practice sessions. The 20-round capacity provides significantly more rounds on tap compared to standard 10- or 15-round factory magazines, reducing reload interruptions during extended shooting sessions.

ProMag has been a long-established manufacturer of firearm magazines and accessories, offering spare and replacement magazines for a wide range of popular handgun and rifle platforms at a value-oriented price point. The GLKA21 is engineered to factory specifications for reliable feeding with 9mm Luger ammunition and includes a full-length steel internal reinforcement, a steel spring, and a polymer follower for consistent performance. It is designed as a drop-in spare or replacement for Glock-pattern 9mm pistol frames, giving shooters a budget-friendly option for building out their magazine collection.