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Synology 4Bay Expansion Kits (Rack Type)


Supports creating volumes across different units:

  • 22 series:RS822RP+, RS822+
  • 21 series:RS1221RP+, RS1221+
  • 20 series:RS820RP+, RS820+
  • 19 series:RS1219+, RS819
  • 18 series:RS818RP+, RS818+
  • 16 series:RS816
  • 15 series:RS815RP+, RS815+, RS815

Create Supporting volumes on a single unit only:

  • RS217

Drive Bays: 4

Compatible Drive Type:

  • 3.5″ SATA HDD
  • 2.5″ SATA HDD
  • 2.5″ SATA SSD

Maximum Internal Raw Capacity: 64 TB (16 TB drive x 4) (Capacity may vary by RAID types)

eSATA Port: 1

Power Supply Unit / Adapter: 100W

Fan Speed Mode: Full-Speed Mode, Cool Mode, Quiet Mode

Packaging Content:

  • Main Unit x 1
  • User’s Guide x 1
  • Accessory Pack x 1
  • AC Power Cord x 1
  • Expansion Cable: Infiniband X 1


Easily add 12 bays to your DiskStation

With its 12-bay desktop form factor, the DX1215II provides generous storage expansion for Synology DiskStation1 whenever needed with minimal impact on the deployment footprint.

Online volume and storage expansion

Add a new volume to your storage, or seamlessly expand RAID volumes on Synology DiskStation without reformatting drives with online volume expansion through DiskStation Manager (DSM) to minimize service disruptions.

Expand DiskStation with Synology drives

Developed in tandem with Synology storage systems, Synology enterprise storage drives deliver proven interoperability and high reliability through rigorous validation and compatibility testing.