CMMG Mk4 platform with Radial Delayed Blowback in 9mm using Colt-pattern SMG magazines. A dedicated 9mm AR with closed-bolt reliability. Type: Carbine Action: Semi-Automatic Caliber: 9mm Luger Capacity: 30 Year introduced: 2015, USA Weight: 112 oz Overall length: 32" Status: Active Intended use: Home Defense, Sport Shooting, Competition