The US Model 1840 non-commissioned officer's knife is distinguished by its over 70-year history of service in the American Army, where it saw action in the Mexican-American War, the Civil War, and the Spanish-American War, among others. A key feature is its light weight, achieved through a wide fuller that allows for agile handling of the single-edged blade. The blade is made of carbon steel (1085), while the accompanying scabbard is made of steel. The weapon is completed by a polished cast brass hilt with a kidney-shaped thrust guard.