Western Digital Ultrastar 7K4000, 20 PK internal hard drive 4 TB 7200 RPM 64 MB 3.5" SAS

HGST Ultrastar® 7K4000 is the world’s first 4TB 7200 RPM
hard drive with a 2.0 million hours MTBF specification
and backed by a full 5-year warranty. Ultrastar 7K4000
represents the sixth-generation HGST 5-platter design,
which has been field proven by top server and storage
OEMs and Internet giants. Engineered for the highest
quality, the Ultrastar 7K4000 is put through grueling design
tests during development and must pass stringent ongoing
reliability testing during manufacturing. Ultrastar 7K4000
delivers by reducing downtime, eliminating service calls
and minimizing TCO.