Manufacturer: American Tactical Inc Action: Semi-Auto Barrel Finish: Black Phosphate Barrel Length: 16″ Caliber: 5.56x45mm NATO Capacity: 30+1 Detachable Magazine: Y Dimension: 4.00 X 14.30 X 42.50 Grips: Black Polymer Hand: Right Handguards: M-Lok Magazine Capacity: 30 Metal Color: BLACK Metal Finish Colored Metal Finish Group Black Overall Length In Inches: 34.25 Rate Of Twist: 1:8 Receiver Finish: Black Receiver Material: Aluminum Upper receiver material : Aluminum Stock Color: Black Stock Description: Adjustable Stock Finish: Black Stock Finish: Group Black Stock Material: Synthetic