This engine is particularly important in the history of FIAT's Grandi Motori division as it represents the first model characterized by "modern" efficiency values (up to 260 g/HP/h) and it is one of the first FIAT 2-stroke engine. The experiences gained in the study and construction of this engine have proved to be very useful for the development of the further model destined for both military and commercial applications, which allowed FIAT to reach a renowed position in the field of naval engines. Built by FIAT San Giorgio in 1909, the engine on display was used, paired with another identical unit, in the Medusa submarine of the Regia Marina. In 1915 the submarine sunk during a war mission and its wreck was recovered in 1958, when FIAT purchased and restored the engine for display purposes, to show its fifty years long activity in the naval sector.