DSI 2.4GHz Wireless Keyboard with Optical trackball, Black, FK-760 Built in optical technology trackball, 800 DPI 2.4 GHz F, 8 Channels, Effective 30ft Range Hot Keys: Pre-Page, Next Page, WWW, E-Mail,My Computer, Pre & Next Track, Play & Pause, Stop, Mute, Volume UP & Down Embedded scroll wheel, right and left buttons, Joystick type left button