Pat-Says-Now Kitty 3-Button USB Optical Mouse Advanced 3-Button Optical Scroll technology provides precision control Plug-and-Play Convenience - Just connect the mouse to your USB or PS/2 port; FREE adapter included! 800 DPI Optical Sensor - High resolution for powerful and smooth tracking performance No mouse ball - Works on virtually any surface, no cleaning or mousepad needed 3 Year Manufacturer's Warranty