This adapter fits all 9/16″-24 LH threaded barrels, when installed
allows the use of all 5/8″-24 threaded barrel devices or accessories.
This is the adapter for your FN FAL and other 9/16-24 left hand
threaded barrels, converting the thread to standard 5/8-24 to allow the
use of your 5/8-24 threaded SUPPRESSORS, Brakes and other devices.