Sensing method: New-generation of Advanced optical tracking Resolution dpi: 1000 Total number of buttons: 3 Scroll Wheel: Yes Tilt function: No Unifying-ready: Yes Battery: 1-AA Battery life: 18 months* *Battery life may vary based on user and computing conditions. Operation distance: 25m (around 80 ft) maximum* *Distance may vary based on environment. Wireless system: Advanced 2.4GHz wireless technology Connection I / F: USB