Hi, Shvegel,
Simple question but no easy answer
230s and early 250s (upto 002979) have 111 290 0215. This has a very short (50-60mm) rubber tube resevoir to pipe to the m/cly and is a different diameter at each end.
I can't find the part # for the resevoir for later cars, but it uses a simple tube with the same dia. at both ends and is longer, maybe 75-80mm.
It's hard to tell the difference between the two when on the car. Both pix RHD cars
What VIN is your car?
Naj
P.s:
The black topped ones are Schafer but there are ATE ones too!