This 8 round magazine is for the PT-22 pistol in .22 long rifle. It is constructed from heat-treated blued-steel, with a follower, lock-plate, and base-plate molded from a proprietary DuPont Zytel based black polymer.ProMag magazines are designed utilizing traditional stamping and welding of heat-treated high carbon steel. Every ProMag magazine is backed by a lifetime guarantee against manufacturer's defects. Features: Magazine body constructed of heat treated carbon steel with black oxide finish Injection molded magazine follower Magazine spring formed from heat treated chrome silicone wire Made in USA