What this off white knob inside the headlights for?
 

Nothing in the owners manual or online that I can find. 🤔

http://986forum.com/forums/uploads02...1671476806.jpg

I am not sure what it is for but when I did my headlight upgrade if you turn it it unlocks that lower ball and makes it easier to pop out.

Turn the knob
 

Take the knob off to fill with high beam fluid.

That's just one of the 3 holders for the reflector bowl in the halogen headlights. In the Litronic lights, the motorized piece goes in place of that white part. The motorized piece raises the xenon low beam when the high beam is activated and when the suspsension sensors send a signal to raise or lower the low beam. My theory is they used that white piece just so they could use the same mounting as the Litronics without the Litronics motoized piece.