- 16” M4 1-8 twist barrel
- 5.56 NATO Chamber (Will shoot 223 or 5.56)
- 7075 T6 Forged Upper Receiver
- M4 Carbine Length Hand Guard
- A2 Flash Hider
- Railed Gas Block
- Forward Assist & Dust Cover
http://www.joeboboutfitters.com/And..._Upper_Receiver_Wi_p/ander-74603-up-nobcg.htm