Model LE6920SOCOM Carbine .223 Remington/5.56mm 16.1 Inch Step-Cut Barrel Matte Black Finish Rail System Collapsible Stock 20 Round Features flat top receiver with Back Up Iron Sights and ambidextrous controls. 16.1 inch chromed step-cut barrel with 6 grooves and a 1:7 inch right hand twist. Matte black finish. Knights Armament rail system. Direct gas system; locking bolt. Bayonet lug and flash hider. Flip-Up adjustable front and rear sights. Collapsible stock. 20 round magazine capacity.