Complete built upper receiver:

  • 16″ M4 profie, 4150 chrome vanadium lined barrel, chambered in 5.56NATO with a 1:7 twist
  • Low profile gas block
  • Carbine length gas system
  • 15″ keymod handguard
  • Flat-top mil-spec Cerro upper receiver with installed dust cover and forward assist
  • No BCG or charging handle

Direct Link: https://3crtactical.com/product/ar-15-carbine-upper-16-m4-5-56-17-barrel-15-keymod-rail/