The quintessential control knob for all USB computers. It spins like a knob and it clicks like a mouse but it's so much more! PowerMate is programmable to control practically any Mac or PC software application. Comes with presets for a wide range of applications and easy-to-follow instructions for adding your own. Use PowerMate to speedily shuttle through large multimedia files spreadsheets word processor documents... great for DJing. Connect as many as 127 PowerMates and assign an independent function to each of them! You can even control the behavior of the pulsing LED in PowerMate's base to give you system status at a glance.