Blue LED - Navigate your computer anywhere, on virtually any surface with precision and control without the annoyance of it not working. Multi-surface - Blue LED technology allows this mouse to be used on a glass* desk surface, granite counter tops, hardwood floors, or even airport carpeting. Contour shape - Use this mouse comfortably for hours with ergo- friendly shape and easy grip surface. Wireless - Plug in the Nano receiver and forgot about it! The small receiver plugs into your laptop's port and can stay; no need to plug and unplug bulky receiver or deal with cords. Low Power – Efficient low power consumption requires only one AA battery *Blue LED technology may not work on some glass or mirrored surfaces.