This brake was designed by two of the best precision rifle shooters in the country, Austin Orgain and Clay Blackketter. The main intent and goal behind the design of the brake was to give shooters a better sight window through recoil, all while being easy on the shooter. Recoil reduction is fine and dandy, but staying on target means more to a match shooter than anything else. You need to be able to see where every single bullet goes, hit or miss. This brake was obviously tested on larger calibers but was specifically made to be absolute perfection on the BR based cartridges. 

All brakes are threaded 5/8 x 24.

More information can be found here:  ACE Muzzle Brakes