ASICS Hera Quarter Running Socks 81% Nylon/13.5% Tactel Nylon/5.5% Elastane Anatomically correct left and right foot construction and high density cushioning Articulated arch band for better fit and ASICS exclusive ankle fit Flexible horizontal lace pad cushioning. "Y" heel gore for improved fit, reducing slippage. "Y" heel gore for improved fit, reducing slippage.