Comparing: M18 Hellcat vs. AT 8

Development started in 1942. In April 1943 the General Motors company produced the first prototypes. One of a few American tank destroyers manufactured on its original chassis, not on a tank chassis. The tank destroyer became the fastest armored vehicle, of this type, of World War II. A total of 2,507 vehicles were produced from July 1943 through October 1944.

The vehicle was conceived as a breakthrough tank. The design project evolved from the AT-7 project, and both projects were submitted at the same time. No prototypes were built because the A39 Tortoise was preferred.