We mapped the movement and impact of a runner's foot to create these socks that cushion, hug, and breathe in all the right places. Designed for Run. 3D-knit PerformaHeel creates a shaped fit and locked-in feeling. MacroPillow medium cushioning. Reflective details. Left and right toe construction for a comfortable fit. All: 94% Nylon, 5% Elastane, 1% Polyester.