ProMag Industries Magazine, 5.7X28MM, 55 Round Drum, Fits FN Five Seven IOM/USG Pistol, Polymer, Black DRM-A76 ProMag magazines are designed utilizing both traditional stamping and welding of heat-treated high carbon steel" and modern precision injection molding of mil-spec polymer compounds. Every ProMag magazine is backed by a lifetime guarantee against manufacturer's defects. Made in USA