The Smartwool Wintersport Full Cushion Mountain Moose Pattern Over The Calf Sock - Youth is a tall sock for comfort inside their ski boots. Built for small feet that seek big mountain adventure, this full cushion sock features medium thickness throughout. It's toasty warm, soft against the skin, and regulates temperature. The Merino wool, nylon, recycled nylon, and elastane blend is stretchy, breathable, and resists odors.