SKI THE SLOPES WITH EASE. The PhD Ski Medium Pattern Sock offers extraordinary warmth and breathability in cold conditions. With Indestructawool technology for durability and the 4Degree elite fit system to prevent bunching and slipping, this sock keeps you going run after run. FEATURESIndestructawool utilizes a proprietary yarn and construction method which strategically places Merino and reinforcement fibers where they are needed most. The result is the most durable and comfortable wool sock ever made.4 Degree elite fit system uses two elastics for greater stretch and recovery to keep the sock in placeMesh ventilation zones designed specifically for male skiers provide optimum temperature regulation and moisture managementVirtually seamless toe14 overall height63% Merino Wool, 35% Nylon, 2% Elastane