The iso series of shoes are engineered to make you want to run isofit consists of a soft inner sleeve and floating support cage that combine to create a dynamic fit system that adapts to the shape and motion of your foot pwrgrid provides more cushioning than standard midsoles while maintaining fluid transitions for a smooth ride a zealot uses these technologies in a lighter weight and lower profile 57gm lighter than the triumph and built with a 4mm offset runners will love how light fast