I like that these socks are very easy to swim in, very flexible, but I don't like why they are so flexible. They are a bit too thin to keep me warm in water below 60 degrees. They worked great for getting into and out of the lake during my long swims, I have tender feet. I wear a 9.5 to 10 size running shoe but have very low-volume, medium width feet so I ordered a small. They fit perfectly. I would say they fit just slightly big. I will look for thicker/warmer socks but keep these for regular use in open water swimming in warmer conditions.

I love these socks for open water swims if the entry is rocky or muddy, or if the water is extremely cold, or if it's a long distance to/from the transition area.  They are easy to slip on and off, feel secure, have a nicely reinforced bottom, and work well.  I am on my second pair - the first lasted about three years before wearing through (I swim about once/week where the entry has gravel/rocks/mud).   I'm constantly recommending these to other people first getting into open water swims.

kept my feet from becoming too cold in an hour swim in 58deg water.  not too tight on my size 9 feet

Worked great!

These worked perfect in the sub 60 degree water temperature.  They are stretchy enough to fit different size feet.  I wear a 9 1/2 shoe and bought the small.  A great piece of swim gear to own!

I used it  in Lake Michigan and the water temp was 52 degrees , it kept my feet much wormer. I ordered a pair of small sox, I wear mens 8.5 to 9.5 shoes and these fit very good. I like that they did not feel loose, felt like i wasn't even wearing them.