I had to grip with my toes to keep them on when walking. This bike rack is okay but it has some problems. My $5 sandals from Target were more durable and didn?t warp at all despite being left under sun and rain for longer periods. The Z racks are better designed, better built and will honestly handle nearly anything you throw at them. Everything is still extremely comfortable. Truly disappointing, I really wanted these to work -- but I will be returning these tomorrow. Hope this review helps your decision. High quality for the price. With the air holes my feet can breath and I don?t have to deal with socks and sneakers. Now, a month later they have settled on my feet.