The Shield Arms S15-COMBO-G3-3M-1C signifies an innovative, patent-pending 15 round magazine designed expressly for the Glock 43X and Glock 48. Remarkably, even though the S15 is a steel magazine with the same length as the default Glock 10 round magazine, it can accommodate 5 additional rounds. So, what distinguishes the Gen 3 magazine? Several enhancements were incorporated, all aimed at maximizing your experience. First, it\'s being manufactured by a reputable US-based manufacturer and utilizes modular tooling. It also features raised ribs at the rear end of the magazine, ensuring perfect alignment with the OEM magazine position in the firearm\'s mag well. This reduces tolerance stacking brought about by variations in Glock frame dimensions. Apart from alterations to the design itself, the Gen 3 magazine introduces a better version of steel, now slightly thicker and more resilient. This new steel is treated with a novel black nitrocarburized QPQ finish, offering a superior level of corrosion resistance. The result is a high-quality magazine that effectively complements your Glock 43X or Glock 48.