The German A7V tank prototype was completed and demonstrated in April 1917 and went into operation in March 1917. Only 20 A7Vs were built. The A7V was armed with six 7.9 mm MG08/15 machine guns and a 57 mm gun mounted at the front. The crew was usually sixteen soldiers and two officers (commander, driver, mechanic, mechanic/signaler, six machine gunners, six loaders, main gunner and loader. The A7V had 20 mm of steel plate on the sides and 30 mm on the front, however the steel was not hardened armor plate, which reduced its effectiveness. It was thick enough to stop machine gun and rifle fire, but not larger calibers. This model shows the A7V tank named Mephisto, the sixth tank built (serial number 506). Mephisto went into action in March 1918 during the assaults around the French town of St Quentin. Following this attack, 506 acquired the name Mephisto and a painting of a devil (Mephistopheles) running off with a British tank under one arm on its front amour. The next engagement occurred when the Germans attempted to capture the village of Villers-Bretonneux in late April 1918. Mephisto and 13 other A7Vs took part in this operation. Mephisto successfully cleared the British front line before advancing on a fortified farm in Monument Wood near Villiers-Brettoneaux. At some point Mephisto was driven into a deep shell crater where it became firmly stuck and was unrecoverable. Mephisto remained stranded at Monument Wood until July 1918, when Australian troops of the 26th Battalion AIF pushed the Allied front line past Mephisto's position. It was recovered by Allied forces on the night of July 22, 1918 and taken to Vaux-en-Amienois before being shipped to England in January 1919. It was later decided that the tank should be displayed as a war trophy in Queensland, Australia. Mephisto arrived in Brisbane aboard the S S Armagh in June 1919. On August 22, 1919 it was towed Queensland Museum in Gregory Terrace. Mephisto still exists today and is the only surviving original A7V.