“Battle Arms Development WORKHORSE, Upper Receiver Assembly, 223 Remington/556NATO, 16″ Barrel, Mid-length Gas System, Anodized Finish, Black, A2 Flash Hider, WORKHORSE 15″ M-LOK Free Float Handguard, Does Not Include Bolt Carrier Group or Charging Handle WH-UR-16-556” has been added to your cart. View cart