I bought these as a replacement for my 3179 model which was becoming old. at first use, they feel a bit big on the face, but you tend to get used to them.they are feather light and the lenses are really nice and protective especially that they are polarized.the only thing that works me is that even though the fit my bold head perfectly I fear that with frequent use they will get loose. I was disappointed to notice that just a few days after I bought them, their price had dropped even more :(