Item Type: Perpetual Motion Machine Material: ABS, stainless steel Gross Weight: 584g / 20.6ozProduct Size: 150x150x100mm / 5.91x5.91x3.94in Battery Type: Built in lithium battery (shipped with built in battery) Battery Model: 18650 Battery Capacity: 1800mah 1、Unique Design: The iron perpetual motion machine is simple in shape, unique and intricate in design to keep the ball rolling and amaze your friends, suitable for toys and decorations. 2、Durable Material: The perpetual motion machine is made of premium ABS material, and the wire is made of stainless steel, which is colorful and durable. 3、Desk Decoration: A classic desk accessory perfect for home and office desk decor, it adds elegance to your home or helps you relax. Perpetual motion machine is a gift for your friends, family and colleagues, it has a fun and attractive design. 4、Toy for Children: It is very suitable for children to enjoy the charm of scientific physics, improve their ability to explore scientific mysteries, and bring them great fun and curiosity. 5、Upgraded Features: Safe and stable, easy to use, one key to open, one key to close. Quiet, continuous use, touch switch. Battery capacity 1800mA, fully charged can work for 4 to 5h.