Large finger-controlled trackball True cordless freedom for desktop flexibility Reliable digital radio technology that requires no line of sight Forward and back buttons for faster Inter navigation Scroll wheel and drag-lock button for easier maneuverability Patented optical technology delivering smooth tracking and superior precision Virtually maintenance-free 72" pointing devices wireless operating distanceInter Service Provider (ISP) account required for full WebWheel software functionalityCompatible with Windows, Mac and Linux. or later3-year limited warrantyIncludes wireless receiver USB to PS/2 adapter and 2 AA batteries