Thread: YHM flip up sight allen screw size?

Help! I'm trying to remove a YHM flip up front sight/gas block and I'm having a problem with the right size allen wrench. 1/8" is to big and 3/32" seems to loose. All the allen kits I have go from 1/8" to 3/32". Is there a special size that guns use? Or YHM uses?

Answered my own ? I looked at the Yankee Hill website and it says 7/64"