Discrete an easy to mount on any lace-up shoe (can be used with non-laced shoes by using the Mono hook accessory). Flexible — uses recoil action with the elastic band and hook. Design helps raise the foot after toe-off reducing the risk of tripping. Universal — fits left or right foot. Can be worn indoors when used with the foot band. Easily cleaned with a damp cloth. Suitable for children. Measure circumference of the ankle.