The Rapid-Thread Muzzle Brake is a robust and efficient suppressor attachment for our Whisper suppressor on barrels with a diameter greater than .775" behind the front threads. The hardened, Melonited steel construction in conjunction with the suppressor acts as the initial blast baffle and reduces internal suppressor wear. With the suppressor detached the Rapid-Thread Muzzle Brake is among the most efficient muzzle brakes on the market and effectively eliminates the bulk of muzzle rise. The Rapid-Thread Muzzle Brake comes with a complete shim set for proper timing on your rifle barrel threads and a rubber O-ring for use with the Whisper suppressor