Smallest internal drive?

Of the currently available bare internal consumer writers, which is physically the smallest. Ideally i’d like something 150mm W x 150mm D x 22mm H

Do you mean “shortest”?

Maybe some Liteons…

how about this one but not in US currently
http://www.plextor-europe.com/products/PX-DB608AL.asp?choice=PX-DB608AL

Is an rebadged Pioneer.