ProMag magazines integrate a blend of traditional heat-treated high carbon steel stamping and welding, along with modern precision injection molding using Mil-Spec polymer compounds. Specifically engineered for Sig Sauer P365 pistols chambered in 9mm, these magazines are constructed from robust heat-treated steel and feature a durable black oxide finish. Each ProMag magazine is supported by a lifetime guarantee against manufacturer's defects, ensuring reliability and longevity for shooters who demand consistent performance in their firearms.