This is a Taurus® 1911 Commander .45 ACP 8-round magazine.
Designed for use with Commander-style 1911 pistols, these Taurus factory magazines feature a standard 8-round capacity with steel construction, steel internal springs, and tough polymer baseplates for maximum durability and reliability. Living up to the reputation of one of America’s favorite semi-automatic pistols without ever breaking the bank, Taurus’ 1911 is a practical, high-performance alternative with the same high-quality fit, finish and feel of a custom pistol. While they’re compatible with most mil-spec 1911 pistols, these magazines are optimized for superior fit and finish with Commander-style Taurus 1911s.