How much depth does the NXT battery pack add? The NXT rechargeable battery pack does not fit flush with the back of the NXT brick like the battery cover (used with 6xAAs) does.  I don't have the battery pack (yet), so I was wondering how much depth it adds.  I found a picture of the pack installed, which gives the impression that it may be a brick taller, or maybe only a stud taller.  Exactly how much though?
It adds the same thickness as a studless beam indeed, or 8mm / 20 ldu.

(This is true for the grey 9VAC battery, but I suppose it holds for the white 10VDC one as well)