R107 side mirror rubber thingie retaining ring
thingiverse
See discussion here: https://www.benzworld.org/threads/rubber-thingies-on-side-mirrors.3060331/page-5 This needs to be printed in flexible plastic (e.g., Ninjaflex) so it can be popped into the hole in the side-view mirror chrome triangle piece on a R107 Mercedes. This fits in my '79 450SL, but seems like there is more than one version of the triangle piece, so can't say for sure if it works on other model years. I printed it with the bigger diameter down, with (minimal) support.
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