What kind of hard drive is inside a Western Digital external product?

The drive inside your external hard drive, network hard drive, WD TV, or router enclosure may vary depending on application. There are several things you should know about WD external hard drives:

• Depending on model, the internal hard drive in an external enclosure could be either SATA or native USB.
• We can only guarantee drive capacity. We cannot guarantee a particular internal hard drive model, data interface, rotational speed, or cache size in the external hard drive enclosure.
• Dismantling any single-drive external enclosure to obtain this information will void the warranty of the hard drive.
• Interface and cache of the hard drives inside the external enclosure does not affect the performance or the data transfer rate of the external hard drive unit.

Note:

With the exception of Thunderbolt, eSATA and USB 3.0 external hard drives, USB 2.0 and Firewire 400/800 have yet to approach the transfer rates of the internal hard drives we use in our external enclosures.

In case the answer did not answer your question, you can always visit the WD Community for help from WD users.