Outer boots: made of particularly tear proof kangaroo leather velcro fastener for different calf sizes two plastic sliders at places subject to particular wear highly elastic areas at instep and heel abrasion resistant PU foam padding for long durability special racing sole with extremely rounded heel plastic sole abrasion resistance (screwed on) Inner boots: aramid/plastic hard shell shock-absorbing padding four layer shinbone protection shock-absorbing insoles in the calf and heel areas robust plastic hard shell with hinged joint aramid/elastic stretch zone anatomically formed spherical heel bed triple aramid-reinforcement left in toe area forefoot reinforcement sweat-absorbing leather lining