Battery Free Wireless Optical Mouse does not need the battery to keep powered on. It works with its partner - the Ingenious Mouse Pad. The Mouse Pad transfers instant & constant power to the mouse as a replacement of batteries. This is we so called: The Electromagnetic Induction Technology. Wireless Optical Technology delivers high resolution with pinpoint accuracy . Enjoy the freedom to go Wireless without any tangling wires . Enjoy a clean and organized computing environment. The core of Battery FREE Technology , the Ingenious Mouse Pad , transfers the power inductively and powered on the Battery FREE Wireless Optical Mouse. The Mouse Pad is specially designed to be waterproof and does not warm or heat up after constant long period of usage . Moreover , its small to be portable , just the right size for mouse to operate upon. AS light as feather without the heavy weight batteries. Provides a safe working environment with 125KHz frequency.