Gas Piston System - 5.56 NATO (Accepts .223 Remington) - 16 Barrel - 1:7 Twist Rate - 30 Round Magazine - Forged 7075-T6 Aluminum Upper/Lower Receivers - M4 Feed Ramps - Beveled Magazine Well - Two Position Gas Plug - One Piece Piston - Integrated Strike Face Anti-Tilt Bolt Carrier - Enhanced Trigger Guard - Magpul 6 Position Collapsible Stock - Magpul Polymer Pistol Grip - Barrett Enhanced Free Float Rail with M-LOK - Barrett 3-Prong Muzzle Device - Flip Up Iron Sights - Overall Length 33.25 - Overall Weight 7.2lbs - Cerakote Black Finish