This barrel is constructed from stainless steel. Includes the complete barrel assembly, a forged and hard coat anodized flattop upper receiver, ejection port cover, forward assist, M4 feed ramps and a 1 in 9 twist. Does not include threads for a flashider and no bayonet lug. 11 degree target crown. No FFL required. Easy installation--remove 2 pins, insert upper and replace pins.