Easily add 12 additional drive bays to Synology Flash Station or Rack Station. Supporting both 2.5 & 3.5 SAS/SATA drives the RX1217sas is a flexible solution supporting on-the-fly volume expansion or serving as a local backup destination. Dual power supplies ensure continuous service uptime. Easily replace defective drives with the hot-swappable drive trays. Key Product Info 12-bay 3.5/2.5 SAS/SATA expansion Maximum reliability design Product Features. 12-bay 3.5/2.5 SAS/SATA expansion Easily add 12 additional drive bays to Synology Flash Station or Rack Station. Supporting both 2.5 & 3.5 SAS/SATA drives the RX1217sas is a flexible solution supporting on-the-fly volume expansion or serving as a local backup destination. Maximum reliability design Dual power supplies ensure continuous service uptime. Easily replace defective drives with the hot-swappable drive trays..