The DX517 is a 5-bay desktop expansion enclosure that adds storage to a Synology DS1819+, DS1817+, DS1817, DS1618+, DS1517+, DS1517, DS918+, DS718+, DS218+ or NVR1218, for on-the-fly volume expansion and local backups. Its five drive bays are hot-swappable and screwless, supporting 3.5" and 2.5" SATA drives, and it connects to the host via an included eSATA expansion cable. An AC power cord and accessory pack are also included, backed by a 3-year limited warranty.