This Sig Sauer Magazine is a factory original replacement part, manufactured to the same specifications and tolerances using the same materials as the OEM magazine that came with the pistol, guaranteeing optimal fit and reliable operation. When it comes to semi-automatic firearms, the ammunition feeding device often determines if, and how well, the gun functions. Therefore, whether for use as a backup mag for your concealed carry pistol or simply for saving a little reloading downtime at the range, keeping a few spare factory magazines handy is never a bad idea. This Sig factory magazine fits Sig Sauer P938 pistols chambered in 9mm Luger. It comes equipped with an extended base pad that not only adds extra length to the tiny gun's abbreviated frame for a better grip and recoil control, but also adds an extra round the magazine's capacity for a total of 7-rounds. While not as concealable as the standard 6-round, flush-fitting P938 magazine, this slightly enlarged version remains unobtrusive and is small enough to be a good choice for carry in the pocket as a backup to the primary magazine inside the gun in the event that it malfunctions or runs dry.