New! The Speed Bump on top features a new, non-sticking rubber to reduce friction and increase durability New! Higher rand profile to provide more structure and add more spring into every step Premiere shoe for speed climbing Syn Flex upper provides great comfort to performance ratio Medium-Stiff midsole running from heel to toe Low Volume version offers a narrower toe box, smaller heel cup, and a lower profile Vegan Friendly TECHNICAL DETAILS Stiffness Medium Upper Material Syn Flex Closure Slipper Rubber Science Friction 3.0, R2 Rand Rubber, Speed Bump Toe Patch Midsole 1.8mm polycarbonate midsole Profile Performance Asymmetrical Curvature Moderate UK Sizing Upsize 1 full size to find your US size