High Definition Laser Technology gives the Mouse more precision, more responsiveness, and smoother tracking Mouse & Keyboard 2.4 GHz Wireless Technology connects wirelessly right out of the box with virtually no interference Advanced Ergonomic Design promotes a more natural hand, wrist, and forearm position for greater comfort System Requirements - Windows Vista, Windows XP Professional, Home, Media Center Edition Mouse fits your hand as naturally as a handshake Tablet PC Edition, 60 MB free space, USB port and CD drive