This Rifle Supply M4 Complete Upper features a 16" ..556 Nato Barrel, Mil-Spec upper receiver, the bolt carrier group and charging handle. Just add a complete lower to complete your project.
Features:
-CALIFORNIA PROPOSITION 65 WARNING:-WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information: www.P65Warnings.ca.gov