This is the factory Glock 9mm and .40 S&W +2 magazine extension with the extension insert.

Please note to properly function, the magazine extension must be used in conjunction with the extension insert. 

This magazine extension and insert works on the following magazines:

• Glock 17
• Glock 19
• Glock 22
• Glock 23
• Glock 27
• Glock 31
• Glock 32