Please note: This product does not include hard drives and SSD Product description 1.Support reading 2 sata 2.5 ''/3.5 '' hdd/d at same time. 2.Hard Drive Duplicator Function(offline clone function) 2-Bay HDD Enclosure its Standalone Duplicator Dock lets you duplicate/clone an existing hard drive without the use of a host computer system, or can be connected to a computer system for use as an external hard drive dock. Product feature .On/Off power switch. .LED light indicates Power and Activity status. .Hot-swappable, plug and play, no drivers needed. .Transfer Rates Up to 5 Gbps w/USB 3.0 .System requirement:for OS X,for Linux,Windows 2000/XP/Vista/7/8/10 (Both 32-bit & 64-bit versions),Android(Smart TV) Package content .HDD docking station .User manual .USB 3.0 data cable .Power plug About Clone Function : 1. *Back disk(B) must be larger capacity(eliminate space lo) than front disk(A) *Plug in identify Source Disk(front port) and Target Disk(back port) *Connect power supply and switch on power. (make sure that the usb cable is disconnected) 2.To avoid your disk file demaged,pls don't stop the device when it's under clone function. 3.When copy disk,pls make sure disk B is empty,or the former file in disk B will be lo.if disk B has file before,and just want to copy from disk A,pls don't use copy function,just copy and paste on computer) 4.When copy the disk,pls don't connect the computer,if connect the computer,disk will be under reading,can not support copy(device heating is normally,as big hard disk operate will be hot) Q&A 1.Q:Can not copy? A:First,device heating is normally,as big hard disk operate will be hot,and even no disk,the device need heat diipation;Second,the back disk must be larger than front one,as you see that,the capacity space maybe wastage,The disk is 320G,but the real capacity may just 310G. My idea is you can check the available space of back disk,and try to remove some file from front disk,then try to copy from front disk to back disk again. 2.Q:How to format more than 2TB hard drive? A:1.Pls make sure the disk is divide by GPT way instead of MBR. 2.Pls don't divide the disk by any other Third party software. 3.Pls make sure if the the driver is install well. 4.Pls try it on windows 7 at least. 3.Q:Can not read the dsk formatting after? A: 1.Pls separate the disk again to make sure if there any unreadable space,and try another format like FAT32/EXT4,not NTFS. 2.Pls use disk identify software to check how larger is the disk.