Features: 1. The magic ball is made of high-quality material, wear-resistant, not easy to break, reusable and durable. 2. Reduce Separation Anxiety: Rollerball is designed to keep your pet busy, reducing stress when you ignore them. It's perfect for when you're at work, have important tasks, or just relax and enjoy some quiet time. 3. Promotes strong mental health: It’s not uncommon for our dogs to get bored, especially when they’re home alone all day. Designed with interactive features to stimulate your pet's natural instincts to play, it's perfect for keeping our pet happy and energized! 4. Built-in battery powered motor: It will roll automatically from inside the motor. Just unscrew the ball, insert an AA battery, click the button on the top, and watch your pet play for hours on end! 5. Automatic movement and interaction: the sweeping plush ball will automatically roll! Its unique interactive features spark your pet's curiosity and keep them engaged. 4 Machine Washable Covers Included: Each ball includes 4 different machine washable covers. Notice: 1.Actual color may be slightly different from the image due to different monitor and light effect 2.Please allow 1-3cm deviation due to manual measurement Description: Material: plush+reusable plastic Size: 13.5*13.5*13.5cm Power supply: 1 AA battery (not included) Package List: 1 set x Magic Rolling Ball (with 4 colors plush cover)