Full-size Px4 Storm in 9mm with 4-inch barrel and full complement of Px4 features including rotating barrel, ambidextrous decocker, and interchangeable backstraps. The foundational variant of the Px4 family. Type: Pistol Action: Semi-Auto Caliber: 9mm Luger Capacity: 17 Year introduced: 2004, Italy Status: Active Intended use: Duty / Defense