Western Digital offers its factory-refurbished Western Digital My Book Duo 12TB External USB 3.0 Hard Drive, model no. WDBLWE0120JCH-NESN, for $459.99 with free shipping. That's the $106 under the lowest total price we could find for a new one. It features two 6TB hard drives, 290MB/s data transfer speed, and two USB 3.0 ports. A 6-month Western Digital warranty applies.