What drive is inside the 3Tb My Book Essential?

Just wondering if anyone has taken apart their 3Tb My Book Essential. (Model  WDBACW0030HBK) and could tell me what the model is of the HDD inside.  The reason is that I purchased two WD30EZRX 3Tb drives from an Amazon seller to put into a NAS device but when I went to register these two drives, they both came up as coming from a My Book Essential.  I just want to make sure there isn’t anything else fishy going on since I was expecting OEM HDDs.

Thanks for the help!

There’s no way to know, you can buy 2 drives side-by-side and open them and they’ll have different drives, check this link…