0TS1854: Western Digital Ultrastar DC HC550 16TB 7200 RPM SATA 6Gb/s 512e 3.5-Inch Enterprise Hard Drive
Also listed as: WUH721816ALE6L4, Ultrastar DC HC550 16TB SATA, 0TS1855 · made by Western Digital
The Western Digital Ultrastar DC HC550 16TB (model WUH721816ALE6L4) is a 9-disk helium-sealed enterprise hard drive engineered for hyper-scale cloud data centers and high-density storage arrays. Incorporating Energy-Assisted Magnetic Recording (EAMR) technology and a triple-stage actuator (TSA), it offers 2.5 million hours MTBF and sustained transfer speeds up to 262 MB/s. Used hardware buyers should verify SMART attributes 5 (reallocated sectors) and 197 (current pending sectors), check power-on hours, and confirm the helium integrity flag indicates 100%.
Specifications
| Part number | 0TS1854 |
|---|---|
| Brand | Western Digital |
| Made by | Western Digital |
| Type | Hard drives |
| Other numbers | WUH721816ALE6L4, Ultrastar DC HC550 16TB SATA, 0TS1855 |
| Status | current |
| Capacity (GB) | 16,000 |
| Interface | SATA 6Gb/s |
| Form factor | LFF 3.5in |
| Speed | 7200 rpm |
| Cache (GB) | 0.512 |
| Generation fit | Universal 3.5-inch enterprise server and storage drive bays |
About the 0TS1854
0TS1854 is Western Digital's enterprise-class 16TB 7200 RPM SATA 6Gb/s 3.5-inch hard drive in the Ultrastar DC HC550 series, bearing model number WUH721816ALE6L4. Utilizing a 9-disk helium-sealed design with Energy-Assisted Magnetic Recording (EAMR) and a triple-stage actuator, it delivers sustained data rates up to 262 MB/s with a 2.5 million hour MTBF rating. It sits in Western Digital's nearline cloud storage tier, replacing older 12TB and 14TB models.
Compatibility
The drive fits standard 3.5-inch large-form-factor (LFF) hot-swap drive bays in enterprise servers and external storage expansion shelves from Dell, HPE, Lenovo, and Supermicro. It interfaces with SATA 6Gb/s controllers, SAS/SATA HBAs, and hardware RAID controllers. It does not fit 2.5-inch small-form-factor drive bays. Host controllers must support 48-bit LBA addressing for capacities exceeding 2TB.
How to identify a genuine unit
Genuine units feature an Ultrastar DC HC550 label displaying Western Digital model WUH721816ALE6L4, part number 0TS1854, 16TB capacity, and 512e sector format. In system BIOS and smartctl, the drive identifies as WDC WUH721816ALE6L4 with Western Digital firmware. OEM-branded variants (such as Lenovo 4XB7A13911) carry OEM label overlays.
Buying used
Check SMART attributes using smartctl, specifically inspecting power-on hours, reallocated sectors (attribute 5), current pending sectors (attribute 197), and helium level status (attribute 22). Verify that the drive is formatted with standard 512-byte sectors and that the 3.5-inch mounting screw threads are intact.
Reference prices (last 14 days, updated 2026-10-27)
New: USD 270 (1 sighting, Oct 2026)
Used: USD 165 (1 sighting, Oct 2026)
All sightings
| Seller | Condition | Price | Note | Seen |
|---|---|---|---|---|
| serversupply.com | new | USD 270 | 2026-10-27 | |
| ebay.com | used | USD 165 | 2026-10-27 |
Prices seen on public listings on the dates shown, before tax and shipping. Not an offer.
Fits these models
Equivalent part numbers
- Lenovo 4XB7A13911 ThinkSystem 3.5" 14TB 7.2K SAS 12Gb Hot Swap 512e HDD ThinkSystem 3.5 16TB 7.2K SATA 6Gb Hot Swap 512e HDD
FAQ
What recording technology is used in the HC550 16TB?
CMR (Conventional Magnetic Recording) with Energy-Assisted Magnetic Recording (EAMR).
Is this drive filled with helium?
Yes, it uses Western Digital HelioSeal technology.
What is the cache size?
512MB high-speed multi-segmented DRAM cache.
Buying or selling 0TS1854?
New, refurbished or used. Tell us the quantity and condition and we connect you with a vetted reseller in your region, usually within one working day.
Sources
- Ultrastar DC HC550 Hard Drive Data Sheet, checked 2026-10-27