Kensington KeyPad 2-Port USB Hub:For anyone who has to manage numbers, data, or spreadsheets on the road. No more hunting and pecking on your notebook computer to run the numbers. With the unique Kensington Pocket KeyPad, the familiar 17 key format input pad lets you fly through numerically-based tasks. No need to carry a separate calculator! Plus, in true Kensington style, this is not just a convenient keypad, but also serves as a USB hub, with two built-in USB ports that allow you to connect other USB devices to your notebook. The Kensington Promise: 1 year warranty with free technical support. Requirements: USB port. Windows 98 or later, or Mac OS 8.0 or later.