Product Description The ProMag Ruger Mini-14 40-round magazine is built for high-capacity shooting with a durable steel/polymer hybrid design. It fits Ruger Mini-14 rifles chambered in .223 Remington / 5.56x45mm and features a steel upper with a polymer lower housing for a balance of strength and reduced weight. A precision-formed, heat-treated chrome silicon wire spring and injection-molded follower help promote consistent feeding and dependable operation. Made in the USA, this magazine is backed by ProMags lifetime guarantee against manufacturers defects. Product Highlights 40-round extended capacity magazine for Ruger Mini-14 rifles in .223 Remington / 5.56x45mm Steel/polymer hybrid construction with steel upper and polymer lower housing Proprietary DuPont Zytel-based polymer components for durability and impact resistance Injection-molded follower and heat-treated chrome silicon wire spring for reliable feeding Made in the U.S.A. and backed by a lifetime guarantee against manufacturer defects Specs Brand: ProMag Industries Product Type: Rifle magazine Compatibility: Ruger Mini-14 rifles Caliber Compatibility: .223 Remington / 5.56x45mm Capacity: 40 rounds Construction: Steel upper, polymer lower housing Polymer: Proprietary DuPont Zytel-based polymer Finish: Black oxide (steel components) Follower: Injection molded Spring: Heat-treated chrome silicon wire Country of Manufacture: USA Manufacturer Part Number: RUG-A46 UPC: 708279016233 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 products manufacturer.