This B&H Kit
comes with the Synology DiskStation DX213 2-Bay Expansion Unit
and two 3TB hard drives
. The included DX213 expansion unit is the perfect solution for volume expansion and data backup for selected Synology DiskStation models. It seamlessly scales up the storage capacity of the DiskStation by adding two 3TB hard drives on-the-fly, for a total of 6TB of additional storage, when connected directly via an expansion cable.