The face of warfare was changed forever on 15 September 1916, when the British first employed tanks at the battle of Flers-Courcelette. From those unreliable, lumbering machines have evolved today's high-tech main battle tanks, which represent the most powerfully concentrated weapons systems on the battlefield. This site intends to present specifications on armored vehicles produced by the United States. A disclaimer must be added that while it may be tempting to become fixated with figures such as armor thickness and gun caliber, we must not forget that the most important part of any armored vehicle is its crew.