Verdict

These are closely matched NAS drives of the same capacity - decide on price and warranty. Check the live $/TB above.

WUH721816AL5204
WD Ultrastar DC HC550 · 16TB · Enterprise
No ES price yet
WUH721816ALE6Lx
WD Ultrastar DC HC550 · 16TB · Enterprise
No ES price yet

Value at a glance

Capacity
WUH721816AL5204 16 TB
WUH721816ALE6Lx 16 TB
Noise (idle)
WUH721816AL5204 20 dB
WUH721816ALE6Lx 20 dB

Price history

ES · cheapest per day

WUH721816ALE6Lx €490
zoomed · drag to zoom
€1,125 €722 €320 Sep 2024 Feb 2025 Jun 2025 Nov 2025 Mar 2026 Aug 2026
WUH721816AL5204 WUH721816ALE6Lx
Capacity 16 TB 16 TB
Recording tech CMR CMR
RAID / NAS safe Yes Yes
Class Enterprise Enterprise
Spindle speed 7200 RPM 7200 RPM
Cache 512 MB 512 MB
Noise (idle) 20 dB 20 dB
Fill Helium Helium
Interface SAS SATA
Failure rate (AFR) - 0.98%
Price / TB - $43.40
Buy No ES price yet No ES price yet

Highlighted cells mark the stronger spec for a NAS build. Failure rates from Backblaze Drive Stats where available; $/TB uses the cheapest live price. Buy links are Amazon affiliate.

WUH721816AL5204

No Backblaze failure data for this model.

5yr warranty · 550 TB/yr rated · 2,500,000h MTBF

WUH721816ALE6Lx

0.98% AFR vs 1.41% fleet avg

95% CI 0.89-1.08%

29,680 drives · ~44,209 drive-years · 435 failures · Backblaze thru Q2 2026

5yr warranty · 550 TB/yr rated · 2,500,000h MTBF