Full size contoured shape; soft rubber grips; curved sides & broad palm area 1600 dpi with Blue Trace technology for smooth precise tracking on almost any surface Two Windows 8 hot key side buttons for charm menu & application switching Consistent wireless connection with reliable 2.4 G Hz technology Smart power management with; wake up; ON/OFF switch & low battery indicator Self-storing Wireless USB (Universal Serial Bus) Nano Receiver Windows 8 Optimized Blue Trace Technology Blue Trace Technology combines the power of optical & the precision of laser for remarkable tracking on more surfaces. Works on almost every surface including granite, counter tops, wood or glass. Tracking Technology on Glass Normal environment glass surface dust density is about 15.54%. The Blue Trace Technology can work well on the transparent glass with dust density of above 9.93%