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These REI CoolMax(R) EcoMade(TM) Multisport low socks are dependable performers for running, cycling, hiking and all of your activities. CoolMax EcoMade fabric offers the same moisture-wicking, quick-drying performance as regular CoolMax, yet is made of recycled PET polyester. Nylon adds durability while spandex offers stretch and shape retention; the snug fit will remain, wash after wash. Lightly cushioned bottoms and heels add shock absorption and protection from wear. Mesh-knit instep panels promote airflow and help move moisture away. Heels and toes are reinforced to increase longevity. Lin Toe(R) "no feel" seams preclude irritation and chafing along toes. Closeout.