10.5 4150CM Nitride-Coated Barrel - .750 Carbine-Length Gas System - Diamond-Honed Nitride M16 BCG - APF 4.5 lb. Drop-In Trigger - APF Adjustable Gas Block - SBA3 Pistol Brace - Magpul MOE Grip - APF 9 M-Lok Handguard - Billet Receiver Set - Ambidextrous Controls - Caliber/ Gauge: 5.56 NATO - Barrel Length: 10.5 4150CM Nitride- Coated Barrel (1:7 Twist) - Action: Semi-Auto - Front Sight: Rear Sight: None - Color: Blue Shark Gray - Finish: Cerakote - Material: Aluminum - Hand: Right