The story of this Assault Gun began in Finland on August 19, 1943 during World War II. In the Continuation War in the summer of 1944, the armoured fighting vehicle belonged to the 2nd company of the Assault Gun Battalion of the Armored Division. In counter-attacks in Tali-Ihantala and Vuosalmi, "Aili" destroyed five enemy tanks. The Assault Gun served as the command wagon of the commander of the 2nd company in the late summer of 1944.