New 300 AAC Blackout. Aero Precision receivers. The Barrel 16 inches, itis Top of the line, made by AAC (Advanced Armament Corp.) The inventor of the 300 Blackout round. Treated with their proprietary black nitride. Barrel was $400 alone. It has a Fail Zero Nickel Boron Bolt Carrier Group. Comes with the sight and Magpul Gen 3 windowed 30 round magazine.