Ergonomically engineered to help optimize your body's alignment, natural movement & energy; Ultra-light, all-day cushioning Anatomicush midsole with flex grooves across the bottom to let feet move freely; RTG-version has slightly deeper cushioning made from a new extra-light EVA foam; Natural arch support; Grip suited to everyday use/road tread; Debossed FitFlop logo on tongue & back of sole; Recycled materials - upper/footbed lining, laces (100% recycled polyester); Suede is Scotchgard protected