The DigiMate III is a card reader that can be equipped with a 2.5 inch HDD.
With the HDD you can use the DigiMate III to copy content from Sony memory sticks or MMC cards on the go. Measurements of the DigiMate III are 112x 75x25mm. The card reader with HDD also features a color touch screen to make the copying of files easier.The battery life is 2 hours. You should be able to use for instance the 2.5 inch 60GB HDD from Toshiba in the DigiMate III.
USBGeek sells the DigiMate III for $49.00.
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