WDBACW0015HBK-NESN My Book Essential 1.5TB

I’m am attempted to determine the drive type that was installed, along with the RPMs and Cache buffer?  I have check the WEB, WD site and cannot find these specifications.  Anyone have this information?

No one has reliable information.

WD can, in theory, put ANY type of drive in an external enclosure.   Could be any number of WD drives in there.

For that reason, WD has a KB article explaining that.