Recycled polyester performance fibers improve moisture management and increase durability, creating socks that will last Inner layer is made of smooth, undyed, hydrophobic recycled polyester, nylon and LYCRA® spandex to maximize moisture wicking for cool, dry feet Outer layer of recycled polyester, nylon and LYCRA spandex and mesh weave enhances moisture control and airflow Interaction between inner and outer layers absorbs friction and shearing forces to prevent blisters Mesh panel for enhanced airflow and cooler feet creates breathability for all-day comfort Stabilizer Zone™ in arches locks socks in place to reduce slipping throughout the day Made in USA.