Fit & Design: SUPPORT FOR THE LONG RUN. When you're on the run, you want padding for miles. The Nike Spark Socks deliver, with a secure and breathable fit made for your workout. Cushioning underfoot gives you the comfort you need for the journey ahead. Underfoot cushioning helps provide support where you need it most The arch is designed so you can wear the sock on the left or right, letting you find the right fit and cushioning for each foot Spandex in the heel provides a stretchy and secure feel. It's designed to help keep your foot supported as it hits the ground Mesh at the top of the foot helps provide ventilation Reflective stripe around the sock Not intended for use as Personal Protective Equipment (PPE) Additional Details: Machine wash