A variant of the heavy tank developed in the U.S. from May 1940, this vehicle featured a cast hull and hydromechanical suspension with a two-disc hydraulic converter. The vehicle was standardized on May 26, 1942. A total of 9 vehicles were manufactured (8 serial and 1 experimental), but never saw action.
HVS1
Wright G2X M781C9GC1
SCR 508
M6D1
3-inch Gun M7
HVS2
Wright G200 M781C9GC1
SCR 538
76 mm Gun M1A1
76 mm Gun M1A2
M6D2
90 mm Gun M3
Characteristics are specified for vehicles with crews trained to 100%.