SEBURO MN-23 - Fixing rear sling hook
Destination
Strengthen up rigidity to hook the sling.
Operation
Take off the sling hook from FA-MAS's butt plate.
Force the hook to make thread M4x0.7,though wire diameter of the hook is φ3.5mm, because it is difficult to get the Nuts M3.5.
Pass it through the holes positioned in Stock Handle, then screw up with washer.