Brain Bending Effect: You immediately notice minute grinding lines and smooth surface texture when you touch the spinning sphere, creating the optical illusion of a continuous flowing spiral and providing a captivating experience Solid sphere: Made of aluminum, helical grooves are ground along the entire surface, can be rotated in any plane, the swivel base is equipped with bearings to ensure smooth, quiet rotation, long lasting Dynamic Swing: Spin the optical illusion ball, it changes pattern with direction and rotation speed, enjoy different visual effects from different angles, each installation is designed with attention to the smallest detail Creativity and Imagination: Continuous silence and smooth rotation, stay focused, relieve stress, cure autism, mind bending illusion, provide an outlet for restless hands to keep your mind focused on the task in front of you. What you will receive: 1 Optical Illusion Ball, 2" (~5.1cm) in diameter, 1.7" (~4.3cm) high, 7 oz (~198.4g) in weight, just the right size to fit in the palm of your hand The best choice for solid tabletop toys you want to use, with lifetime technical support