Wisdom Pro Flex Interdental Brushes have a unique flexible handle designed to reduce the potential of wire breakage, giving longer lasting performance. The curved shape of the handle helps to improve access to difficult to reach areas at the back of the mouth. Use regularly to help keep your teeth and gums healthy, to protect against gum disease and tooth decay and to keep your breath fresh. Never force the brush into a space. Keep out of the reach of children. Excessive force and bending of the wire can lead to breakage which can cause injury.