The 24" blade is a smidge too long. And I have found that the 23" is in short supply for some reason, but that's the correct size for the W124.

If the auto supply shops can't keep any around, the dealership should have them readily available.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car