As early as 1926 various German companies, including Rheinmetall and Daimler-Benz, produced a single prototype armed with a large 75-millimeter cannon (the Großtraktor, "large tractor", was so codenamed to veil the true purpose of the vehicle).
Xa a comezos de 1926 varias compañías alemás, como Rheinmetall e Daimler-Benz, fabricaran un prototipo armado cun gran canón de 75mm (chamado Großtraktor, "gran tractor", para agochar o verdadeiro propósito do mesmo).