The Armaspec FDE Spring Loaded Takedown Pivot Pins are designed for AR-15/M16/M4 rifles made from lightweight aluminum. These pins feature a convex head for tapping from any angle an extended concave tip for easy removal using any flat or pointed object and an EZ-Set hole for detent installation. They include a dimpled end for easier push and are mil-spec with a .250 dimension. The package comes with one pivot pin one takedown pin two detents and two detent springs. These pins are proudly made in the U.S.A. and come with a lifetime warranty.