Salming Viper 3.0 Shocking Orange Men's Squash Shoes fabric-and-leather RollBar: An increased radius on the inner side of the outer sole, facilitates rolling the foot inwards and toe push off. T.G.S. 62/75 (Torsion Guide System): The distance from heel to the ball of the foot has been designed with extra stability, which ends in the "ballet" line. In front of this line Salming has equipped the shoe with greater flexibility to stimulate the foot's natural movements ExoSkeleton: The exo skeleton design stabilizes the foot for lateral movements and reduces pressure at the Metatarsophalangeal joints Ergo Heelcup: To stabilize and fixate the heel, Salming has developed a new anatomical Ergo Heel Cup that is slightly longer than the average heel cup XR110: The outsole has an extra sticky compound to maximize performance on any indoor court