Mark V, Mark V*, Mark VIII, Ford 3ton, M1917, FT17, and Steam Tank, Holt Gas Electric Tank, Caterpillar Tank (which might have been only a movie mock up), Tiny Holt Rhombus Tank, Skeleton Tank, Studebaker Tank, Best 75 Tracklayer, Holt 3 Wheeled Steam Tank, Holt Tracklayer CLB 75.
Are there any more that at least made it to prototype or mock up stage for the USA in WWI?
Add the Hamilton or Victoria. Several photos, no explanation of name.
The Caterpillar G9 was a film prop.
Have we done the Ford 3-Man? One prototype only.
And the 150 ton Field Monitors.