The Synology RX1217sas is a 12-bay Expansion Unit for use with Synology FlashStation and RackStation units. This expansion unit seamlessly adds 12 additional 2.5" or 3.5" SAS/SATA drives to offer a volume expansion unit or backup destination. The RX1217sas is covered by Synology's 5-year limited warranty and Synology Replacement Service This item may not be available for immediate delivery. Please check with us before purchasing as it could take 7-10 days to fetch from Synology. Suitable for use with: - FS3017 - FS2017 - RS18017xs+ N.B. Connecting to a Synology FlashStation FS3017 requires the optional FS3017 Expansion Card (FXC17) to be installed on the host device. FS3017 Expansion Card is sold separately. Please note that Synology boxes are supplied without hard drives. We recommend the WD Purple HDDs for this product. Hardware Guide Learn More