The SIG MPX is a 9mm pistol-caliber carbine adopted by FBI SWAT and other law enforcement agencies. Uses a closed-bolt, gas-operated design derived from the MCX rather than a blowback system, providing better accuracy and reduced noise when suppressed. Type: Semi-Auto Rifle Action: Gas-Operated Caliber: 9mm Capacity: 30 Year introduced: 2015, USA Weight: 6.5 oz Overall length: 28.5" Status: Active Intended use: Law Enforcement, Special Operations