The 2021 Swiftwick Pursuit Four Sock is constructed with nature’s technical fiber Merino Wool and upgraded with a reinforced heel and toe to maximize durability. The four season fiber of Merino Wool provides warmth in the winter and cooling in the summer, as well as absorbs moisture without feeling soggy or losing the ability to regulate temperature. The Pursuit is engineered with fine-gauge Merino Wool that produces a soft, no-itch feel from cuff to toe. Merino Wool is a naturally renewable resource and is sustainably sourced. The Four height sits below the calf and its double-cuff construction provides extra support for cycling and trail running.