The Soviet KV-1 heavy tank was a shock to the invading German forces in June 1941. Its thick armour made it all but impenetrable to German anti-tank fire, forcing extreme measures like direct fire artillery to be used to destroy it. However, it had one big drawback. It was more expensive to produce than the T-34, but had the same 76.2mm gun and worse mobility. Production ended in April 1943 and it was phased out soon after. | The Tank Museum