The next evolution in Smartwool's partnership with iconic alpinist Conrad Anker, the Smartwool Unisex PhD Outdoor Approach Mini Socks bring performance footwear technology to new heights. Designed to fit seamlessly in approach or hike footwear, these socks offer our 4 Degree elite fit, comfort, and Indestructawool technology for durability to handle demanding approaches, day hikes, and every day wear.