Civilian version of the USSOCOM MK18 CQB rifle with a 10.3-inch barrel and Daniel Defense RIS II rail. Direct impingement. The MK18 is the standard close-quarters carbine of US Navy SEAL teams and Army Special Forces. Type: Pistol Action: Semi-Automatic Caliber: 5.56x45mm NATO Capacity: 30 Year introduced: 2015, USA Weight: 6.4 oz Overall length: 26.75" Status: Active Military use: Yes Intended use: PDW / Military / Collector