helped get rid of glasses fog
These work great to keep my mask on comfortably and snugly enough to not constantly fog up my glasses, without needing the mask to hook only my ears.  Plus the button adjustment thing (whatever it's called) makes it super easy to hang the mask around my neck when I take it off.  I have not seen anything in stores that does this, so if you struggle to get masks to fit comfortably, this may help.
Rating: 5 stars