These are so cheap I bought a few pairs for me and my son.  They were really too small for my face so he wore them all...and broke them all.  They only last about a week.  The same problem kept happening the screws fall out.  Given what I paid I'm not that upset or surprised but these are pretty poor.  They look cheap as well.  Very cheap looking plastic and scratch very easily.  Even as cheap as they are I would stay away.