This is a factory 9-round magazine for Glock 27 pistols
These 9-round standard magazines feature a flush-fitting baseplate and numbered witness holes for keeping track of capacity. They’re engineered for optimum fit & function, and designed to drop free when released.
ONLY fits 40 S&W ammunition and Glock 27 pistols.
Glock magazines come with a very strong spring rate from the factory to ensure reliability in the toughest of conditions. Sometimes, magazines are found to be a little bit difficult to load at first. However, after a few times loading and unloading, the springs break in nicely and it becomes much easier to load.