ProMag Industries Magazine, 308 Winchester/762NATO, 40 Rounds, Fits SR25 and DPMS Pattern AR10, Polymer Construction, Flat Dark Earth DPM-A4-FDE 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.