Sizing is wrong, no instructions or photos of how to wear.  Would not hold my mouth shut.
I have a huge head (7 7/8 hat) and it is still too big, I think.  There are no instructions in the box or on the box.  I scoured the internet, including the Raschify web site, and could not find one photo anywhere of someone wearing this actual device so I could see if I might have been wearing it wrong.  I have tried it on every which way and it is still too big to hold my mouth shut, which makes it totally useless for me.  Even though it does not work, the material is pretty comfortable though.
Rating: 1 stars