WD DC HC550 18TB 7.2K SAS 12Gbs 512MB 3.5" HDD WUH721818AL5204 0F38353 Tested
About this item
Overview
The Western Digital DC HC550 is an enterprise-class, 3.5-inch CMR hard drive designed for high-capacity NAS arrays, SAN environments, and data center workloads. The 18TB capacity makes it an excellent choice for high-density storage builds running TrueNAS, Unraid, or similar platforms. These are genuine enterprise pulls - not re-branded consumer drives - and are rated for 24/7 operation with a 2.5 million-hour MTBF.
Interface note: this is a SAS 12Gb/s drive. It requires a SAS host bus adapter, RAID controller or SAS backplane (LSI/Broadcom, Dell PERC, HPE Smart Array and similar) and will not work on a SATA-only port or in consumer NAS enclosures such as Synology or QNAP without a SAS controller.
Technical spec sheet
How we test used storage drives
This describes our testing process. Contact us for available unit-specific results before ordering.
- Step 1SMART health review
Reallocated, pending and uncorrectable sector counters read from the drive itself.
- Step 2Extended self-test
The drive's own long self-test, run to completion.
- Step 3Power-on hours cross-check
Hours compared against the drive's internal logs. We never reset counters.
- Step 4Wiped
All previous data is wiped and the wipe is verified.
- Step 5Tamper seal and certificate
Sealed after testing with a numbered tamper-evident seal. Its QR code and the certificate in the box open this exact unit's report.
Condition notes
These drives are used pulls from a datacenter environment. Each unit has been individually tested prior to listing:
- SMART Long Self-Test: Passed
- Power-On Hours (POH): 18,000 - 29,000 hours (range across available units; specific POH for your unit may vary within this range)
- Reallocated Sectors: 0
Zero reallocated sectors and a clean long SMART test indicate healthy platters and heads. Drive exteriors may show minor cosmetic wear consistent with datacenter use.
Warranty and shipping
Warranty and returns
90-day warranty- Replacement or refund after verified failure, prepaid return label on defective items.
- 30-day returns: defective items ship back on our label, change-of-mind returns pay return postage.
- Compatibility help by email before and after purchase.
Dispatch and packaging
Same-day dispatch on orders before 3PM Mountain- Free shipping to all lower 48 states.
- ESD-safe anti-static shielding bags with heavy-duty crush-resistant padding.
- Full declared value carrier insurance with instant tracking notifications.