Start by confirming correct setup with an alignment rod. Clean all contact points, torque the muzzle device to 15-25 ft-lb and apply Rocksett to secure it to the barrel. Ensure the device is flush against the barrel shoulder. Important - using with a Q can could void your warranty - use at your own risk. When attaching the silencer, clean both threads and tapers thoroughly, then torque the suppressor to 10 ft-lb. Check final alignment before firing. You're good to go. 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