I dont know. I am pretty sure the regulator I had was original. But maybe it was replaced? And maybe that replacement was an update, from another model or form another car?

But the pic of what I have installed are here, so I would be interested if anyone else has the same style as mine. I see there are a couple variations on regulators for a W126.

__________________
1991 560 SEL / 185k miles
1992 750il / 17k miles - project car