Audere Hammerhead Muzzle Brake .338 5/8x24 Matte Black. This series is made of black-nitrided high-grade steel and is designed to deal with the striking amount of gas generated by the most powerful calibers through two specific ports which feature different exhaust angles. Specifications for Audere Hammerhead Muzzle Brake: Manufacturer: Audere Color: Matte Black Finish: Nitride Fabric/Material: High-Grade Steel Features of Audere Hammerhead Muzzle Brake Heavy reduction of recoil and muzzle movements Manufactured from high-grade steel Jam nut included for an easy installation Package Contents: Audere Hammerhead Muzzle Brake Audere HH0003: Hammerhead Muzzle Brake .338 5/8x24 Matte Black