Take Viball in your hand, feel the weight and movement of the inner ball. Now slowly swing the ball back and forth from your wrist: This realistically simulates the maximum movement that your lower body can perform in terms of range of motion and speed.
Fast hand movements or hectic shaking of the forearm are unrealistic, because you cannot perform such extreme and/or wide-ranging movements with your lower body, so the noise produced is not representative. These slight movements create a vibrating noise or a slight clicking sound. The noise is naturally dampened in your body and is much quieter than when you test it in your hand. If you now change the position of the ball a few times horizontally and vertically, the noise also changes. This is because Viball is made up of two halves. During laser welding, a minimal ridge (bulge) is created inside, which influences the path of the inner ball: sometimes the ball rolls along the ridge, sometimes it crosses it and sometimes it even jumps slightly and causes knocking impulses. Even when worn in the body, there is never a constant position: by hitting the ridge and through the movement of the muscles, the outer ball gradually rotates and changes its position. This also causes the stimulating impulses to vary, a very positive side effect, because the body adjusts to constant, constant stimulation after a while and the effect of the stimulation would diminish.