Heavy tank
The Char 2C was one of the largest tanks ever produced. At the start of World War II, France and the Soviet Union were the only countries to have inventories of heavy tanks, such as the Char B1, T-35, and KV-1. The Matilda II was designed under the British infantry tank concept which is similar to the heavy tank having thick armor and weighing more than their other tanks. It’s usually separate because they have less firepower with their cruiser tanks (comparable to mediums) at the time having the same main armament but more machine guns. Later war examples were the German Tiger I and II, as well as the Soviet IS series. Note that "heavy" versus "medium" is more a question of tactical roles than weight; the Panther, for example, was a "medium" tank that outweighed most Allied "heavy" tanks.
Tanks in the Italian Army
The order to design and produce the first Italian tanks was accepted by the FIAT automobile company in 1916. The Fiat 2000 - Model 17 was conceived by Fiat as a private venture in October 1916 and some feel the finest heavy tank built in WW1. The first prototype was ready in June 1917. Fiat donated 2 tanks to Italian Army in February 1918 but the Fiat 2000 never saw combat. Total production until the end of 1919 encompassed 6 vehicles. The prototype of the new tank was displayed to a military commission on 21 June 1917; its mechanical systems were complete but its superstructure was added later, being represented on the prototype by a wooden mockup with a conical open turret and dummy gun. The final configuration of the superstructure was not completed until 1918.The FIAT 2000 was a substantial vehicle, of comparable dimensions to the British Mark V tanks, and weighing 40 tons as compared to the Mark V's 28 tons.