This is a Daniel Defense DDM4 A1 chambered in 5.56 with 16 barrel. Comes with one 30 round magazine. This is in excellent condition. Mounting System PicatinnyCaliber 5.56mm NATOMuzzle Thread 1 ⁄ 2 × 28 TPI (Threads Per Inch)Gas System CarbineBarrel Length 14.5″Barrel Profile M4Length 31 1/2” – 34 ¾”