The upper pattern is a modern-redesign of the original Silver Shadow (1981). Back in 1981, the Silver Shadow was worn by the recruits of the German and British army (MOD). HI-TEC®'s functional Rollin Gait System (RGS) was developed by Vibram in collaboration with the HI-TEC® product team in 2011. The Vibram Rollin Gait System sole unit has an innovative midsole and outsole combination that supports the natural movement of the foot to reduce muscle fatigue.