ProMag magazines are made in the USA and backed by a lifetime guarantee against manufacturers 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.Features :20-Round MagazineFor Glock 17/19/26 9MM PistolsMagazine Body Constructed of a Proprietary Dupont Zytel Based PolymerMagazine Body Has Full Length Steel Internal Insert Stamped and Welded Like The Factory MagazineInjection Molded Magazine FollowerSpring is Made From Heat Treated Chrome Silicon WireMade in the U.S.A.