The thread cutter works like this – it’s a razor blade entirely enclosed in metal. You can wear it safely like a pendant or put it on your chatelaine. I was using this on the airplane long before it became a no-no to take scissors on board. Easy to cut threads, you just run the thread into one of the many notches on the edge. It also will easily open those individual pill packets! I’ve never had this taken from me at any of the airlines and I still use it now instead of risking losing my scissors.