Description of Smartwool Adrenaline Medium Crew This full cushion sock is great for hiking, fast packing or peak bagging, along with any type cold weather training that demands full cushion performance like cross-country skiing or winter hiking. Description: The Adrenaline crew sock provides outstanding all-day fit and high density padding for excellent shock absorbency throughout the activity. This sock also features a full cushion sole for ultimate protection and comfort along with the Smart Fit System that assures great-fitting socks all day long. Features: 67% wool, 32% nylon, 1% spandex