Development was started in 1936 by the Landsverk company. The new vehicle incorporated some elements
of the L-60 light tank. In 1939, Hungary took an interest in the project. By the time the first prototype was produced in 1940, Hungary decided to develop their own medium tank on the basis of the Škoda T-21. Later, some technical solutions were applied in the development of the Strv m/42 tank.