The M1 Abrams is a main battle tank produced in the United States. The M1 is named after General Creighton Abrams, former Army Chief of Staff and former commander of the 37th Armored Regiment. It is a well armed, heavily armored, and highly mobile tank designed for modern armored ground warfare. Notable features of the M1 Abrams include the use of a powerful gas turbine engine, the adoption of sophisticated composite armor, and separate ammunition storage in a blow-out compartment for crew safety. It is one of the heaviest tanks in service, weighing in at close to 70 tons.