This muzzle brake adapter is required for use with the Barrett AM338 adapter mount suppressor. It is made of hardened carbon steel and has .75"x24 threads. The adaptor is not rated for full auto fire. Barrett believes in thinking outside the box and exploring ways to improve. They are a leading manufacturer of superbly accurate long range large caliber rifles, and the accessories to support them.

Specifications and Features
Barrett 16129
Required for use with AM338 adapter mount suppressor
Steel
.75"x24 thread
Not rated for full auto
Black