Hike how you like in the responsibly sourced ZQ-certified Merino wool Hike Light socks by SMARTWOOL. Formerly known as PhD® Outdoor, these hiking socks are packed with all of the best tried-and-true sock innovations, like Indestructawool™ technology for enhanced durability, 4 Degree™ Elite Fit System for a dialed-in, performance-oriented fit, and Virtually Seamless™ toe for even more comfort. Light cushioning along the entire bottom of the foot helps you feel your best on every trail. Extended durability zones and updates mesh areas to help maximize breathability without sacrificing the perfect sock fit in any hiking shoe or boot.