Smartwool&';s Hike Full Cushion Crew socks, formerly PhDA(R) Outdoor, use cushioning on the entire sock to help maximize warmth and protection. These responsibly sourced, ZQ-certified Merino wool hike socks are built with Smartwool&';s top sock tech, including Indestructawool(TM) technology for enhanced durability, their 4 Degree(TM) Elite Fit System for a dialed-in, performance-oriented fit, and t heir Virtually Seamless(TM) toe for maximum in-shoe/boot comfort. They&';ve updated the hike line by improving mesh zones for additional breathability, as well as creating a new ply structure that reduces pilling while enhancing hand-feel and comfort. Not to mention, their best-feeling, best-fitting hiking socks are now made with recycled nylon-making these socks more sustainable than ever. Now that&';s something you can feel good in and about. Features Sock Height: Crew 4 Degree(TM) elite fit system for a dialed-in, performance-oriented fit Additional body-mapped mesh zones for added breathability Virtually Seamless(TM) toe for enhanced comfort Indestructawool(TM) technology with extended durability zones Comfort welt with &';stay put&'; fit Height 8" Made in USA of Imported Yarn: 56% Merino Wool, 11% Nylon, 31% Recycled Nylon, 2% Elastane