5-Bay Expansion Unit DX525 (Diskless)
*Price sourced from Amazon.com. Last updated 2026-07-22. Price and availability subject to change.
Bottom line: The 5-Bay Expansion Unit DX525 (Diskless) is a niche pick — read recent reviews before buying in the external storage category, priced around $519.99. Read recent reviews carefully before committing.
The Synology DX525 allows users to easily add up to five 2.5-inch or 3.5-inch drives to their setup, thanks to its straight forward installation process and DSM’s intuitive volume management software.
SpecPicks Verdict
SpecPicks classifies Synology 5-Bay Expansion Unit DX525 (Diskless) as a niche pick — read recent reviews before buying in the external storage category, based on our editorial and benchmark analysis and our ranking model that weights rating × review-volume × price-fit. Synology's positioning sits within the broader category mid-tier. Use the Compare tool to put it side-by-side with two or three close alternatives before clicking through to Amazon.
Common buyer scenarios for external storage of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.
Pros & Cons
Pros
- ✓ Supports drives on the model's official compatibility list
- ✓ Backed by Synology's warranty and support channels
- ✓ Ships via Amazon with Prime eligibility and the standard returns policy
Cons
- ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
- ✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified
Key Features
- Supports drives on the model's official compatibility list
- Add 5 additional 3.5"/2.5" SATA HDD/SSD to your DiskStation.
- Configure new storage in minutes with Synology DSM's unified toolsA
- Backed by Synology's 3-year limited hardware warranty
- Plug-and-play compatibility and support for hot-swapping drives
Full Specifications
| Size | 166 mm x 230 mm x 223 mm |
|---|---|
| Brand | Synology |
| Color | Black |
| Material | Metal, Plastic |
| Unit Count | 1.0 Count |
| Model Number | DX525 |
| Mounting Type | Tabletop |
| Mfr Part Number | DX525 |
| Compatible Devices | Desktop, Server |
| Enclosure Material | Metal, Plastic |
| Is Assembly Required | No |
| Warranty Description | 3 Year |
| Item Dimensions D x W x H | 8.78"D x 9.06"W x 6.54"H |
Ready to buy?
Synology 5-Bay Expansion Unit DX525 (Diskless) is available on Amazon with Prime shipping and the full Amazon returns policy. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-07-22. Price and availability subject to change.
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