DetailsSize Chart Over 25 years ago, Smartwool invented the original Merino wool performance sock—the Classic Hike. The Classic Hike remains mostly unchanged and certainly unmatched in comfort. But today, it’s getting upgraded. And that upgrade starts with recycled nylon—creating a more sustainable (but just as comfortable) sock. They’re also made with responsibly sourced, ZQ-certified wool that was grown with a focus on ensuring environmental, social, and economic sustainability while also taking the best care of the Merino sheep. This is a cozy, capable classic that is never going out of style.