5.56x45 (223) Chamber. This kit includes Complete M4 upper with BCG. USGI Retractable M4 stock with assembly. Also include a lower parts kit.
Barrel Material: Nitrided
Gas Block: .750" Rail height gas block
Flash hider: A2 birdcage
Reciever: Forged 4140
BCG: Nitrated M16 carrier with properly staked gas key
Charge handel: Standard.
Made in U.S.A.
Magpul upgrade available.