The T-34 series, with its sloping armour, changed the principles of tank design during the war. The sloping, angular layout of the T-34 increased the effective armour thickness, and also saw a larger proportion of shells deflected away than penetrated its armour. The introduction of the T-34 into action saw German tank design follow suit with similarly angled armour on the likes of the Panther and King Tiger. As German tank design came to the fore, the Soviet war machine once again raised the bar with the T-34/85.