Which 3.5 drive do I need for my 2E enhanced?

["John Jacobs" <jjacobs@hager.net>]

Here's a bit from an Apple 2 History web site talking about 3.5 drives...
(http://www.hypermall.com/History/ah09.html)

"Overall, Apple released four versions of 3.5 drives between 1984 and 1986.
First was the 400K drive used on the original Macintosh, then the 800K
UniDisk 3.5 (which wouldn't work on the Mac), then an 800K drive for the Mac
(which wouldn't work on the Apple II), and finally the Apple 3.5 drive,
which worked on the Apple IIGS and the Mac, but not the IIe and original
IIc"

Question: I want to add one 3.5 to my Apple 2E enhanced, so what do I need?
Right now the computer has  two individual 5.25 drives (not the two
connected together unit). I see many 3.5 drives on ebay, but I want to be
sure it'll work with my setup. Thanks!