They grip against your foot for perfect fit. Make your old heels even more glamorous! Perfect for shoes that do not fit comfortably. Perfect for heels which is a little too big they fit right over your shoes so you dont have to worry about them slipping off while walking or dancing at a wedding or hosting an event. Easy to use as the picture, there is a strap that wraps around the back of the heel and there is a strap that comes across the top of the foot and buckles on the side Fit for dance shoes/ high heels/ sandals, etc.