Airborne Arms AAS8 Spectre Muzzle Brake .300 AAC/7.62/6.5/6mm ARC 5/8x24 Threads Per Inch Black Small AAUP-BLS8. The Spectre Muzzle Brakes are precision CNC-machined from a solid bar of stainless steel and coated with a black QPQ nitrocarburized case...