Product Description The ProMag Industries SMI-A17 is an extended 25-round magazine designed for the Smith & Wesson SD40 chambered in .40 S&W. Built with a heat-treated steel body and a durable finish, it is engineered for reliable feeding and long service life. The magazine spring is precision-wound from heat-treated chrome silicon wire, and ProMag backs the magazine with a lifetime guarantee against manufacturer defects. Product Highlights Extended 25-round capacity for fewer reloads during training and range sessions Heat-treated steel magazine body with a durable blued/black-oxide style finish Precision spring made from heat-treated chrome silicon wire for consistent performance Polymer follower for smooth feeding and dependable operation Manufactured and assembled in the USA and backed by ProMag&&';;s lifetime guarantee Specs Product Type: Pistol magazine Compatibility: Smith & Wesson SD40 (.40 S&W) Caliber: .40 S&W Capacity: 25 rounds Body Material: Heat-treated steel Spring Material: Heat-treated chrome silicon wire Follower: Injection-molded polymer Country of Manufacture: USA UPC: 708279012648 Manufacturer Part Number: SMI-A17 Brand: ProMag Industries Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&&';;s manufacturer.