Logitech M221 Wireless Mouse, Silent Buttons

Sensors Sensor Technology: Smooth optical tracking DPI (Minimal and maximal value): 1000± Buttons Number of Buttons: 3 (Left/Right-click, Middle click) Scroll Wheel: Yes, 2D, mechanical SilentTouch Technology: 90% noise reduced Left/Right-click, Middle click*. (*Sound level comparison between Logitech M220 and Logitech M170. Left click dBA measured by an independent lab at 1m.) Scrolling: Line-by-line scrolling Battery & Charging Battery type: 1 x AA (included) Battery life: 18 months*. (*Battery life may vary based on user and computing) Connectivity Connection Type: 2.4 GHz USB wireless connection Wireless range: 10 m*. (*Wireless range may vary based on user, environmental and computing conditions.) Connect / Power: Yes, on/off switch