The Numeric USB Numeric Keypad and Calculator offers desktop and notebook users an instant benefit of a full-sized, external numeric keypad in a compact form. You will not worry to install drivers as it uses USB Plug-and-Play technology. It also features a wide LCD screen and additional function keys to use with or without a PC. You can retract the USB cable and use the built in calculator at anytime. It is slim and portable, definitely designed for mobile professionals. Win 2000, XP, Vista and 7.