This is my second pair of these; the first ones I wore completely out.  I held back one star because the size selection runs small.  I ordered the large for my size ten foot and it is very tight. I am sure it will stretch, but it is uncomfortable now.  If you go to Isotoner's web site, they have a conversion of small, medium, large and extra large to normal shoe sizes....too bad they don't sell these in normal shoe sizes.