The Bellingham Sock from Keen is made from temperature-regulating, breathable merino wool. Seamless toe in flex zone reduces bunching. Extra cushioning on the bottom absorbs impact. Contoured arch provides support. Keen offers right and left-foot specific socks for the best possible fit. Crew sock rises to just below the calf. Mid-weight fabric. 59% merino wool, 37% nylon, 3% polyester, 1% spandex.