Dont know about the W210 but I changed a set of four springs last summer on my 500SEL. There are 3 different thicknesses for my car, the sizes I cannot recall but they certainly determine the ride height of the car and the clearance of the top of the tyre to the wheel arch. What I can recall however is that I could not find a part number on these rubbers in situ but they are covered in the suspension section of the service CD's. Once the springs were out and the rubbers removed, the part number is found on the inside of the rubber ! Good luck...

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1993 190E 2.0L (Euro.) sold
1991. 500 SEL (Euro.)
1991. 300 CE (Euro.) sold
1993. 500 E (U.S. spec.)