X-Gene 2.4GHz Wireless Keyboard w/ Optical TrackBall 01030 2.4 GHz radio frequency with 16 channels USB receiver Ergonomically designed allowing for comfortable use on table or lap. The trackball comes with two-button mouse keys and scroll wheel Working Range: 10 meters 103 keys and 23 Internet /Multimedia hot keys (Must have Windows Media Center for all Media Center Hotkeys to work)