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U.S. Arms M4 Builder Set


ATF regulated items have restrictions and requirements:

  • Your order will ship only to a Federal Firearms License holder.
  • We are not currently shipping to CA, CT, DC, HI, MD, MA, MN, NJ, NY, or VA.
  • Please be sure to contact your local FFL dealer prior to placing your order to ensure they are still accepting transfers. Some FFL dealers are not open due to Covid-19.
  • Customer must read, understand, and agree to customer terms and conditions.


Trigger Guard


Upper Receiver

M-4 mil-spec, stripped

Hand Guard

15 inches, with M-LOK mounting system

Builder set includes these parts:

Note: Cerakote items may require up to 2 weeks processing time.

(Complete rifles shown in photos are for illustrative purposes only. Only the parts listed above are included.)