One size fits most, not all.<br /><br />I like the concept, unfortunately I am one of those for whom they do not fit well.  I have a relatively small/flat nose  These glasses will hold on near the end of my nose, however, in that position they are almost useless for me to read as I'm trying to look almost straight down in order to look through the lenses. Any higher on my nose, and they won't grip because there's just not enough bridge/bridge is too wide for them to grab onto.<br /><br />The lenses themselves are relatively small and narrowly spaced, but, the quality seems good, and I can use them if I simply hold onto the lenses.  This is OK for quickly reading something (label on a can, etc.), but will quickly become annoying to me for extended reading.<br /><br />The carrying case is a nice idea.  It's convenient, and attached to the back of my phone with no issues, thus keeping them handy on my belt when I need them.  After a few tries I can easily remove/replace the glasses from the case with one hand, without looking.