Accurate-Mag AICS Pattern Single Stack Magazine 300 Win Mag 5 Round 3.775" Length. Constructed of hardened steel this SSSF (Single-Stack & Single-Feed) Accurate-Mag magazine is also heat treated for better durability and features a black Teflon finishing for superior longevity. The mag is designed to fit the Accuracy International Chassis System (AICS). This magazine fits the .300 Winchester Magnum round in a single-stack single-feed configuration with a 5 round capacity. Accurate-Mag offers the perfect magazines for any shooter.