Moriarti Ar-15 Rifle Barrett Style Muzzle Brake 1/2x28 Pitch Black MAR-BARR-AR15. 875 in Package Contents: Moriarti AR-15 Rifle Barrett Style Muzzle Brake Moriarti MAR-BARR-AR15: Ar-15 Rifle Barrett Style Muzzle Brake 1/2x28 Pitch Black