Grosstraktor

Grosstraktor (German: "large tractor") was the codename given to six prototype medium tanks built (two each) by Rheinmetall-Borsig, Krupp, and Daimler-Benz, for the Weimar Republic, in violation of the Treaty of Versailles. Constructed in secret, they were tested by Reichswehr units at the Kama tank school in the Soviet Union. They were used for training and retired as monuments after the Nazi party came to power.