Tyrant CNC Mag Extension, Fits Glock 19/23, +5 Rounds for 9MM, Anodized Finish, Gray TD-G19MAGEX-G This Glock-compatible magazine extension for the G19, G23, and G26 offers a more advanced and effective alternative to the limitations of the OEM Glock magazine. While the standard capacity of the G19 magazine is 15 rounds, Tyrant CNC's Glock-compatible mag extension increases capacity by up to 5 rounds. Each purchase includes a 10% power spring and is easy to install with no tools needed.