Experience the benefits of FitFlop in a slipper! A water-repellant suede upper lined with plush shearling surrounds your foot in softness. Help tone and trim your legs while reducing strain on your feet knees and back. FitFlop has been scientifically proven in independent studies to boost overall leg and calf muscle activity. The secret is the varying density of EVA foam in the midsole that generates a Micro-Wobbleboard effect to significantly increase muscular tension. Your legs work harder than they do in standard shoes and you burn more calories.