Florence Modal Men's Ribbed Sock, Model 270. It is described as medium weight as opposed to the model 210 which has narrow ribs and is light weight. This sock is very soft, doesn't fade, and doesn't pill. It has wide ribs and is a mid-calf sock. It is good for feet that sweat a lot. They run very small, probably the average size 10 shoe would wear a size 13-15.