This Fitflop Electra is the flip-flop with the gym built in. Product Features: Flip-flop Sequins covered leather upper Microfiber lining Leg and muscle-toning microwobbleboard midsole Tone and tightens leg muscles while walking Helps increase leg and muscle activity up to 30% Absorbs more shock than a normal shoe Helps realign ground force retention to joints feeling less ache in hips and knees Reduces foot pressure Do Not clean in washing machine/dryer or submerge in water