The M3 shoulder holster, introduced in 1943, was widely used during World War II. Designed for the M1911A1 .45 caliber pistol, it featured an adjustable shoulder strap and a leather belt attachment strap. It was eventually superseded by the more versatile M7 holster. This particular piece, issued to the Marine Corps during the war, bears the stamp “USMC / BOYT / 43” on the reverse. A name is also present, but it is illegible.