ProMag Industries Magazine, 45 ACP, 13 Rounds, Fits Smith & Wesson M&P 45, Steel, Blued Finish SMI-A16 ProMag magazines are made in the USA and backed by a lifetime guarantee against manufacturer's defects. Magazine springs are precision wound using heat-treated chrome silicon wire and each and every step of the assembly process is checked and double checked in order to maintain the same consistent level of quality.