Of the dozen boats built of this class, only one survived World War II.

The Sirena class was an improved and enlarged version of the preceding Argonauta-class submarines.

[1] For surface running, the boats were powered by two 675-brake-horsepower (503 kW) diesel engines, each driving one propeller shaft.

[2] On the surface, the Sirena class had a range of 5,000 nautical miles (9,300 km; 5,800 mi) at 8 knots (15 km/h; 9.2 mph);[1] submerged, they had a range of 72 nmi (133 km; 83 mi) at 4 knots (7.4 km/h; 4.6 mph).

They were also armed with a single 100 mm (3.9 in) deck gun forward of the conning tower for combat on the surface.