Genuine Dell K251D 6-Button Grey Gray Silver Black USB Scroll Wheel Optical Laser Mouse, Works Perfectly With Windows 95, 98, NT 4.0, 2000, XP, Vista, and Windows 7, and Will Work With ANY Computer System That Supports USB Connectors, Compatible Part Numbers: M534D, Y357C, Model Number: M-UAV-DEL8 Package contains mouse with attached USB cord Laser Accurate technology enables mouse to work on virtually any surface USB Plug & Play connectivity Color: Grey Silver/Black 6-button interface with scroll wheel for easy web navigation, Dell Part Numbers: K251D, M534D, Y357C, Model Number: M-UAV-DEL8