The Smartwool Women's PhD Outdoor Medium Crew is an advanced, medium-cushioned hiking sock for women. Thanks to merino wool, the sock has optimum moisture and heat exchange and remains odor-free for a long time. It has a high, elasticated shaft that adapts well to the leg. The sole is fully cushioned and pressure and impact are well absorbed. The 4-Degree Fit System ensures optimum adaptation to the foot. So you run and run and run.