This is the M1934 pistol designed in the 1930s as a new standard Italian service pistol to replace the plethora of revolvers and automatics in a variety of different calibres then in use (and that continued in service anyway).
It was based on earlier Beretta designs, being simple and easy to make but also reliable and compact. The low powered round in 9mm Corto (short)/ .380 ACP and a very short barrel of 3.4 inches/86.4 mm resulted in a weapon suitable only for short range self defence but it was very popular never the less. About 1 million were produced during WW2 and it was used by various Axis countries including Germany as the 'Pistole Modelle 671 (i)'. It was also a sought after souvenir for Allied soldiers.
This example was made in 1942, having the year in Arabic numerals as well as the number 20 in Roman numerals marking the time after the Fascists came to power in Italy in 1922-this was standard practice until the fall of the regime in 1943.