Features of the Icebreaker Men's Ski+ Medium Over The Calf Sock Anatomical toe box for unique left and right Fit Sculptured cushion maximizes Fit and comfort Achilles support keeps your sock in place Ankle support enhances Fit Instep support for stability Seamless toe closure to reduce bulk and prevent blisters Breathe zone for improved ventilation Function junction to eliminate bulk Comfort cuff wide welt for comfort Anatomically sculptured, fully cushioned ski sock Fabric Details 58% Merino, 39% Nylon, 3% Lycra