A lot of 172's came with exclusive on the logbooks - no idea why, but as Daniel has correctly stated, the only Official exclusive model was on the Ph1, which had:
Scarab green paint
exclusive BBS alloys
Cream full leather interior (including door cards)
CD player head unit instead of tape (Still had the CD changer under the seat too)
There were offically supposed to be 172 of them each numbered, but a few made it through very late that were not numbered.
They were also sold in Europe, and most of those were not numbered.