Cinch Lace with Cord Lock for Snug Fit Around Ankle. Cushion EVA Midsole. Flexible 2-Color Lightweight Rubber "Radial" Outsole. Flex-Foam 5mm Bootie with Four-Way Stretch Nylon. Lightweight and Flexible, 100% Waterproof. Full Perimeter Outsole Provides Maximum. Protection to Toe, Arch, and Heel Areas.