Developed on the basis of the Lago medium tank in the 1930s. The 75-mm Bofors gun was mounted on the 22.5-ton tank. A total of 282 vehicles of different variants were produced. The TM, TH, and TV variants used the Scania-Vabis L-603 twin engines, which provided 160 h.p., while the Strv m/42 EH tanks were powered by a single Volvo A8B engine that provided 370 h.p.