Kineti-Tech Clocking Ring with wrench flats 1/2" X 28 Threads
Clocking Ring for directional muzzle brakes.   A clocking ring allows the "clocking" or the tighting of a muzzle brake so ports are directed in the proper direction.  Specs: OD .780 Threads- 1/2"x 28 Material - A311 StressProof