The Toshiba MG04SCA40EA (often listed with part code or internal reference HDEPF22GEA51) is an enterprise-class 3.5-inch hard disk drive (HDD) from Toshiba’s MG04 series.

Key Specifications

* Capacity: 4 TB (4,000 GB formatted)

* Form Factor: 3.5-inch (standard low-profile enterprise design, ~26.1 mm height)

* Interface: SAS (Serial Attached SCSI) 12 Gbit/s (backward compatible with 6 Gbit/s and 3 Gbit/s SAS)

* Sector Format: 4Kn (4K native sectors) — requires OS/host support for 4K sectors (not 512e emulation)

* Spindle Speed: 7,200 RPM

* Cache/Buffer: 128 MB

* Performance:

* Sustained data transfer rate: Up to ~215 MB/s (inner/outer zones vary)

* Average seek time: ~8.5 ms read, ~9.5 ms write

* Average latency: ~4.2 ms

* Power: Dual voltage (5V + 12V), typical operating power around 11–12W

* Reliability Features:

* Designed for 24/7 operation in enterprise environments

* Workload rating: 550 TB/year

* MTTF (Mean Time To Failure): 1.4 million hours

* Unrecoverable error rate: 1 in 10¹⁵ bits read

* Persistent Write Cache technology

* Optional Self-Encrypting Drive (SED) variants in the series (this model typically supports SIE — Sanitize Instant Erase)

* Other: Helium-free (air-filled), RoHS compliant, built for business-critical storage like servers, arrays, cloud, big data, and nearline applications.