The PzKpfw III (Panzerkampfwagen III) is a German medium tank designed by Daimler-Benz AG. The first tests of the vehicle took place in 1936. The construction of the PzKpfw III consisted of four main modules: the turret, the front of the hull, the rear of the hull with the engine compartment cover and the lower hull. The first version of PzKpfw III - Ausf. A - was produced in May 1937. Soon after, the Ausf. B and C versions also entered production. Ausf. D version was introduced in January 1938. Early PzKpfw III models were prototype vehicles and were not suitable for mass production on a large scale. They were powered by Maybach HL 108 TR petrol engines with 250 HP. They were armed with 37mm guns and three MG-34 machine guns (two in the turret and one in the hull).