Proper setup starts with using an alignment rod to ensure everything is correctly aligned. Clean all relevant surfaces, then torque your muzzle device to between 15 and 25 ft-lb and apply Rocksett to lock it in place. It's critical that the muzzle device sits square to the barrel shoulder. Be aware - use on a Q can may void your warranty. Before installing the suppressor, clean the threads and taper surfaces, then torque the suppressor to 10 ft-lb. Confirm final alignment and enjoy safe, accurate performance. 17-4 PH H900 Compatible with Atlas and Atlas XL Compatible with Plan B The Atlas adapter has exceeded the limit by approximately 0.05 inches Atlas XL adapter does not experience overrun Black nitride coating with a surface hardness of 67 HRC