Shop › DEAD AIR KEYMO BRAKE .46 5/8X24 DEAD AIR KEYMO BRAKE .46 5/8X24 $90.00 Dead Air Armament Key Mount, Muzzle Brake, 45 Caliber, 5/8x24, Nitride Finish, Black DA161 Quantity: Add To Cart Added! Dead Air Armament Key Mount, Muzzle Brake, 45 Caliber, 5/8x24, Nitride Finish, Black DA161