1.USB CHARGING: No need to replace the battery. The blue indicator light will be on when charging, and it will be off when fully charged. 2.EXQUISITE DESIGN: High-quality stainless steel shell, sturdy and durable. 3.MULTIPLE FUNCTIONS: 3 different colors modes, 5 patterns. IDEAL TOY for CATS: Ideal for outdoor actives. Small pet interactive indoor Toys. 4.DEEPEN YOUR RELATIONSHIP WITH PETS: Easy to use, you can slide the button and play with pets while sitting on a chair.