[W126 Coupe] Rear Lighting?

[Sam Sisic]

Happy New Year all!!!

I was changing out bulbs in the rear lights and noticed that the innermost cell with a red lens has a hole for a bulb but no wiring/power to it. It's just an inoperative blank cell.
Anyone know why this is? Is this typical for US models where the Euro models have a bulb in this cell?

Just curious...

Sam
88 560 SEC US