The FÉG 37M was an improvement over the earlier Frommer 29M. It was made in 2 chamberings. The .380 ACP (9x17mmSR) chambered version was used by the Hungarian Army, while the .32 ACP (7.65x17mmSR) version was supplied to Hungary's German allies during World War II. The former, was known in Hungarian service as the M1937. The latter, in German service during World War II, was known as Pistole 37(u), pistole M 37 Kal. 7,65 mm or P37. The main difference between this and the other variants is that the "German" version had a manual safety (which the Hungarian issue did not have) and was marked "Pistole M 37 Kal. 7.65" and the FEG code "jhv" and date, along with the Waffenamt markings. Though it was produced under more strain due to the rate by which they wanted them produced, it was still a reliable pistol. 150 - 300,000 pistols were completed this way.