Features: 100% brand new and high quality Supports simultaneous reading of two SATA hard disks, tool-free disassembly and assembly of hard disks, and hot-swappable support. High-speed USB2.0 data transfer rate up to 480MB/sec.USB1.1/USB2.0 SATA I and SATA II are compatible. Support all 2.5' / 3.5' SATA hard disks (maximum support 2TB);The transfer speed of e-SATA interface can reach 3GB/s One-key backup function (only on the USB port) with LED indicator .The offline clone speed can reach 70MB/s Support system (Window98/Me/2000/XP/Vista/7/Mac operating system 9.X/10.x/Linux). Package Includes: 1 x HDD Base Enclosure Specifications: Item: Dual Bay SSD Dock Base DC:12V Material:ABS Size:approx 13x10x7cm/5.11x3.93x2.75in Applicable: IDE/SATA Output interface:/USB2.0 SATA I and SATA II Compatible Capacity:Support 2TB Support:All 2.5 ' / 3.5 ' SATA; USB1.1 Plug Type: EU/UK/US Plug (Optional) The Basic Operation Connect to the hard disk dock and computer with a USB cable. Open my computer, you can see the drive letter, and the red signal indicator light is on when reading the drive. Press the one-key backup button to perform one-key backup. You can use the external e-SATA interface to connect with the computer e-SATA interface to transfer data. When offline cloning, insert SATA hard disks in both A and B positions (A is the main disk, and A is less than or equal to B), turn on the power switch, and confirm that the hard disk is spinning. Then double-click the single-key backup button twice, and the time interval between the two clicks does not exceed 5 seconds. If the red indicator light flashes, it means that the clone is normal. (Note: The USB interface cannot be connected to the computer during offline cloning) note: For the safety of your hard disk data, you'd better not to plug or unplug the hard disk when it is connected to the power source. The e-SATA interface is plug and play and supports hot swap. Please allow 0-1cm error due to the manual measurment and certain tolerances in the product, please understand.