Created in 1994, the Sigma incorporates a pre-set striker firing mechanism. It is available in both .40 S&W cartridge and 9×19mm Parabellum, being one of the first pistols purpose-designed to handle the .40 S&W. Similarly styled sub-compact designs in .380 ACP and 9×19mm were also produced. A limited number of these pistols were also chambered in .357 SIG. The .380 ACP version bore visual similarities to the larger Sigma pistols, but used a direct-blowback operating system and was otherwise unrelated.
Bron: Wikipedia