Assymetrical conus is a simple multi-purpose balance board movable in one plane. Primarily it is intended for the training of ankle stabilization. With choice of anatomical plane in which we exercise, we can provoke isolated rotational movements of the upper or lower ankle joint, whereas the knee must be in stretched position. If we bend our knee, the strategy of balance maintenance will turn to the knee and hips, and the active muscle groups will be closer to the trunk. Asymmetrical conus is an efficient proprioceptive requisite useful in the prevention and rehabilitation of ankle injuries, although, with little inventiveness, we can also efficiently use it in stabilization training of other body segments.