5 shoe, so I purchased size 11 and it fits perfectly. Kinda messes with the sensors too. Mostly I wanted to never have cold feet or ankles, but not have sweaty feet either. Highly recommend these shoes. I have used it a few times and I can hear the other person clearly. I?m so going to be buying a size small to continue my weight loss journey! Comes with all you need to install them. The are far too narrow and my foot is normal even petite in size. My grandson loves this set of hedphones! This is sturdy once assembled and the included rubber prevents scratching.