‘+2 Mag Extensions for Glocks 19/23/32 Glock Full Metal Lined +2 (40 caliber), +3 (9mm) magazine extension is combined with an extra power high quality spring to help in proper feeding. Includes everything you need to increase the capacity of your pre-ban magazine. Please note: the included magazine insert does not have a button-like protrusion to lock into the magazine floorplate. You can confirm proper installation of this factory part by ensuring the floorplate latches onto the two plastic notches on the side of the magazine tube. NOTE: Will not allow you to add rounds to legally restricted 10 round magazines.