Features: 1.Multifunction:It Helps promote feelings of calm, helps reduce stress/anxiety, and helps improve concentration, and also helps hypnotize people who suffer from insomnia. 2.Unique & magical decoration:for your living room, walls, home, dining room, bar, office, hotel,etc.it will attract the look of people and exclaim! 3.Ideal as creative gifts for weddings, anniversaries, housewarming and Christmas. Note: If the steel ball does not fall back to the expected position after starting, please use the tool to adjust the width of the top of the track. Specification: Material: Plastic + Iron Dimensions: 15x10x15 cm / 5.91 x 3.94 x 5.91 inch Power source: battery (not included) Package including: 1x Perpetual motion machine 5x Steel balls