Aero M5E1 upper and lower, Criterion 18" rifle gas stainless barrel, Magpul CTR with Larue RISR, Larue MBT-2S flat trigger, Strike Industries muzzle brake, ERGO Tactical grip. Scope and mount not included. I've only fired a box of 150 grain hunting ammo for sighting in. Shot sub MOA for the one group that I shot with it.