The M60 is a main battle tank developed by the United States as a successor to the M46, M47, and M48 in order to combat the new T-54A tank fielded by the Soviet Union. The M60A1 tank is an improved mass-produced version of the M60, with production beginning in 1960, four years after the prototype of the original M60 was completed.
The turret was changed from the M60's "turtleshell" shape to a thicker shape with front armor and a wider internal volume. The tank's excellent maneuverability, powerful engine and 105mm tank gun L7A1 made it an excellent tank with a good balance of offense and defense; it has become the standard main battle tank for the U.S. military and other Western countries. About 20,000 of this tank have been made, and it has become the best-selling tank.