This is a factory 15-round magazine for Gen 4 Glock 31, 32, and 33 pistols in .357 Sig

While Glock pistols do an amazing job of taming the .357 Sig’s violent recoil, it’s Glock’s factory magazine that ensures optimum feeding & reliability despite constant torture and even in the most extreme conditions …

With capacity for 15 rounds of hard-hitting .357 Sig, these Glock factory magazines deliver serious firepower in a standard-sized package. Made from crack-proof polymer and reinforced with steel inserts, they’re compatible with all .357 Sig Glock pistols.

Fits Gen 3 and 4 Glock 31, 32 and 33 pistols.

Glock factory magazines are built for reliability, and as a result sometimes come from the factory with extremely stiff springs. These springs typically “break in”’ over time, making for easier loading and unloading after the first few uses. 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.

We recommend using a magazine loader to ease the loading process.