Features - * BlueTrack Technology - Microsoft BlueTrack Technology combines the power of optical with the precision of laser for remarkable tracking on virtually any surface. * Comfort and durability - Rubber side grips and a contoured shape for either hand. Dust-resistant design allows you to track confidently. * 5 Customizable Buttons - Reassign any button to fit your needs. Quick access to the media, programs, and files you use most often. * Tilt Wheel - Easy horizontal and vertical scrolling.