Key features Built-in rechargeable Li-ion battery (including USB charge cable) Comfortable thumb rest and rubber coating for perfect grip USB micro-receiver: plug in once never remove again 2 thumb buttons: Browser back & next 1000 dpi sensor for accurate control On-off switch Connectivity Connection type wireless Bluetooth no Wireless protocols RF 2.4GHz Wireless range 10 m Receiver included yes USB version 2.0 Connector type USB