Enhance your firearm's performance with the ProMag Industries SIG-A20 21-Round Steel Magazine, expertly crafted in the USA. This magazine is designed for optimal reliability and precision, ensuring your firearm operates at its best. With rigorous quality checks throughout the assembly process, you can trust the durability and functionality of this product. 21 - Round Capacity Steel Construction Heat-Treated Chrome Silicon Wire Spring Manufactured & Assembled in the U.S.A. Easy Loading Rugged Construction Experience unmatched quality with a lifetime guarantee against manufacturer's defects.