Optical sensor technology - Blue Trace technology combines the power of optical technology with the precision of laser for remarkable tracking on almost any surface including wood, granite and carpet Dual-purpose design - Large enough for comfortable desk use, yet small enough for the mobile user Ergonomic - Ergonomic shape provides support to help prevent palm strain; designed for left and right handed users Self storing adapter - Wireless receiver stores in mouse so it's never loss and always ready to use What's in the box x1 Wireless Blue Trace Mouse