Comfort starts from the inside, out. Naturally insulating, moisture wicking and antimicrobial - Merino Wool and Repreve recycled yarns wrap your feet in cushioned comfort. High-power instep elastic locks in a blister-free fit. Nylon reinforcement yarns at heel and toe boost durability. Lifetime Sock Warranty. We’re so confident in our USA made, sustainably sourced socks that we’re putting a lifetime warranty behind them. If your socks fail, we'll replace them, no questions asked.