I always thought that the single wiper design was MORE expensive to produce than your typical dual arm setup. I'm sure that the cost of the extending and retracting mechanism exceeds the cost of another motor!

My '89 420 SEL (V126) has one blade that follows the other. Great design! Very little sight obstruction that way. Instead of the alternating swish- swish motion, just one fast swish, that really clears the windshield. Best design i've seen.

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"I have spent MOST of the money I have made in my life on expensive women, expensive cars, and expensive drugs. The rest I just wasted." - Myself "Belief in the supernatural, reflects a failure in the imagination." - Edward Abbey "Give me a firm place to stand, and I will move the Earth." - Archimedes