I can see a third thread coming

I know they're not interchangeable but since I'm not familiar with the car, I can't tell by looking which one I have. MB wasn't kind enough to mark it left/right, links/recht or even L/R as far as I can see.

I was also too stupid to save the emails about the deal or remember who gave it to me.

Don, both edges look slanted to me. One more so so I'll guess the side edge gets the more severe slant.

I notice that one lower corner is pointed and the other is rounded.

Thanks,
Sixto
91 300SE
87 300SDL
83 300SD