the polyurethane ball, even it is soft, swings correctly as it is provided with anti-rolling up rope – equipped with adhesive hook - pbdq, ae, sz graphemes are particularly useful in case of dyslexia - training with Marsden ball develops tracking capabilities, increases speed and accuracy as well as body coordination and spatial perception - exercises can be done lying down, sitting, standing, on the balance board in monocular or binocular - adhesive letters can be easily removed or added: the only limit is your imagination