This USB Optical Wheel Mouse utilizes optical tracking technology for precision control. Offered in a full-size shape that fits fortably in either hand this mouse has an integrated wheel-scrolling device that also acts as a programmable third button. There is no mechanical ball to get dusty or dirty. It does not require a mouse pad and works on many types of surfaces.Primary InformationInput Device Type : Mouse Device Form Factor : External Connectivity Technology : Cable Buttons Qty : 3 Movement Technology : Optical Interfaces : USB; USB PC Compatibility : PC Dimensions&MiscellaneousWidth : 2.1 Inch Depth : 4.5 Inch Height : 1.3 Inch Color : Black System InformationMovement Technology : Optical Features : Scrolling wheel System RequirementsSystem Requirements / OS Required : Microsoft Windows 98 / ME / 2000 / XP UNSPSC CodeUNSPSC Code : 43211708