I bought about 6-8pairs of this style seeing as I owned about 20 pairs of the WrightSock Coolmesh double layer low sock. I purchased so many to start replacing my other ones that were starting to wear out.  This was a case where "You don't get the quality you pay for!" This style kept sliding down my foot onto my heel. Such a disappointment for a sock that costs so much! And all I was doing was just walking around, I wasn't even trying to jog or run in them yet, thank goodness!  I didn't return them since I washed them all and didn't wear them right away. I thought I had a defective one at first, but no matter what pair I wore, they would start slipping off down my heel. Perhaps someone else has had better luck than me, I wear a size 7 in women's and I ordered a size medium in this style.