Enhanced version of the M4E1 with improved spring-pin handguard interface and beveled mag well. The upgraded M4E1 upper/lower set. Type: Carbine Action: Semi-Automatic Caliber: 5.56x45mm NATO Capacity: 30 Year introduced: 2017, USA Weight: 112 oz Overall length: 32" Status: Active Intended use: Sport Shooting, Home Defense, Competition