Discover the unmatched reliability of the ProMag Industries SIG-A21 20-Round Magazine designed for the Sig Sauer P365 9MM. Engineered with high-quality materials, this magazine guarantees durability and performance in critical situations. Manufactured in the USA, ProMag magazines boast a lifetime warranty against defects. Each magazine features precision-wound springs and rigorous quality checks to ensure exceptional standards. 20-Round Magazine Fits Sig Sauer P365 9MM Pistol Magazine Body Constructed of Heat Treated Steel with Black Oxide Finish Injection Molded Magazine Follower Magazine Spring Formed From Heat Treated Chrome Silicone Wire Made in the U.S.A. Invest in performance with ProMag-your trusted choice for magazine reliability.