5.56 NATO

Diamondback Firearms, DB15 DIAMOND, Semi-automatic, AR, 223 Remington/556NATO, 16" Barrel, Muzzle Brake, 15" M-LOK S Rail, Black Finish, Magpul ACS Stock, Magpul Pistol Grip, Magpul MBUS PRO Sights, 30Rd PMAG

Ruger, AR-556, Semi-automatic Rifle, 223 Rem/5.56NATO, 16.1" Threaded Barrel, 1/2" x 28 Thread Pitch, Black Anodized Finish, Black Collapsible Stock, Adjustable Flip-Up Rear Sight, Adjustable Post Front Sight, 30 Rounds, One Magazine