Vivian & Vincent 5 Packs of Casual No-Show Ultra Flexible Low-Cut Socks 78% COTTON / 20% POLYESTER / 2% POLYURETHANE, FLEXIBLE. Machine Washable Elastic Comfortable Flat Boat Line Socks of Silicone Anti-Slip Heel Grip 5-Packs for Sale Ultra thin but duarable, Ultra Flexible. For both Adult & Child. Best for spring and Summer