Blued steel construction Music wire spring Steel follower Clear-cut witness holes Precision-engineered feed lips Crafted from durable, corrosion-resistant blued steel, the Auto OrdnanceA(R) M1 .30 Carbine 30-Round Magazine offers unmatched reliability and combat-ready performance at an affordable price. Featuring a corrosion-resistant blued finish, this All-American centerfire rifle magazine features clear-cut witness holes for quick, visual round counts, while the welded steel base plate offers improved durability in harsh environments. The heavy-duty music wire spring offers long-lasting feeding performance and a positive slide stop operation for enhanced reliability, while the low-friction, controlled tilt steel follower ensures smooth feeding operation with virtually no risk of binding. Better yet, this magazine is machined to exact specifications for a consistent, wobble-free fit for added reliability. Founded by the inventor of the legendary Thompson submachine gun over a century ago, Auto Ordnance is dedicated to preserving the heritage of America's most legendary firearms-while continuing to innovate and improve in the pursuit of perfection. Enjoy superior field performance and consistent operation with this historical icon. Order yours today!