What kind of drive is in the WD My Cloud 6TB Single Drive Model?

[Kuromizu]

I'm trying to find out what kind of hard drive is in the WD My Cloud 6TB single-drive model.
Does anyone here know?

I actually have 3 of them here sealed in the box. I don't want to open one to find out because I'm selling them. However, if I find out that they're WD Red, I might keep one lol.

It's this exact model here:
http://www.amazon.com/Cloud-Persona...id=1446676013&sr=8-1&keywords=wd+my+cloud+6tb