Strategically designed with padding in high-impact areas and ventilation where you need it most, the PhD Ski Medium Pattern Sock is equipped to handle a long day in ski boots so you can stay comfortable while hitting the slopes. Merino wool, nylon blend. Over-the-calf height. 4-Degree elite fit system. Reliawool in high-impact areas for optimal comfort and cushioning. Mesh ventilation zones for added breathability. Flat-knit toe seams eliminate irritation.