The German Mauser Tankgewehr was the first purpose built weapon designed for use against tanks.
The Tankgewehr was a single shot rifle, firing an armour piercing 0.512inches (13mm) tungsten alloy round coated with lead in a copper jacket.
This anti tank rifle was used in action in early 1918, its factory output peaked at 300 rifles a day, a total of 15,820 were made by the end of the war.
The Tankgewehr was capable of penetrating 0.866inches (22mm) steel plate at at 328 feet (100 metres) with its muzzle velocity of 2700ft/s (823m/s).
The Mauser 13mm Tankgewehr required a two man team in operation.
Its length was 5 feet 6 inches (1.68m) and its weight 39lbs (17.7kg) with bipod.
Having a very significant recoil it caused many injuries to its operators and was not a popular weapon for this reason.