Durable and portable wireless mice. The ultimate in portability with convenient Nano Transceiver ideal for executives on the road. Featuring Bluetrack™ Technology which combines the power of optical with the precision of laser for superior tracking on virtually any surface*. With a handy battery indicator for when batteries need changing, long battery life lasts over 6 months. Graphite. 3 Years Warranty. Dimensions:7L x 20.3W x 14.3H cm.*Disclaimer: Blue Track Technology does not work on clear glass or mirrored surfaces.