Built on the capable and proven Mk4 AR15 platform this BANSHEE comes with the shortest 9mm barrel CMMG® has to offer making this the most compact 9mm AR that utilizes our 9 AR conversion magazines. - Platform Mk4 - Caliber 9mm - Operating System Radial Delayed Blowback - Barrel Length 5 - Barrel Twist 1:10 - Barrel Contour MT - Barrel Material 4140CM SBN - Barrel Twist 1:10 - Muzzle Device CMMG ZEROED Linear Comp - Muzzle Thread 1/2 X 28 - Upper Receiver Billet 6061 T6 Aluminum - Lower Receiver Mk4 Forged 7075 T6 Aluminum - Hand Guard CMMG EML4 M-LOK - Finish Cerakote Standard - Charging Handle CMMG ZEROED Ambi - Pistol Grip CMMG ZEROED Pistol Grip - Buffer Type Carbine - Receiver Extension CMMG 6 Position Fastback Extension - Stock / Brace CMMG RipBrace - Trigger Type ZEROED Drop-In Single Stage - Trigger Guard CMMG ZEROED Trigger Guard - Safety Selector CMMG ZEROED 60/90 Degree - Magazine CMMG 9ARC 30rd - Weight 4.7 lbs - Length 20.8