Support That Moves. When you're on the run, you want cushioning for miles. The Nike Spark Socks deliver, a secure and breathable fit made for your workout. Underfoot cushioning varies in thickness based on where you need it most. Switch-foot arch support is designed to let you wear your socks on either foot. Spandex in the heel helps secure the fit to keep your foot supported. Mesh at the top of the foot helps provide ventilation. Reflective stripe around the sock. Not intended for use as Personal Protective Equipment (Ppe). 92% Polyester, 8% Elastane.