Someone on this forum claimed that anything not on the DOT list wasn't allowed.
Unfortunately, the only MB trunk-triangle I had, got sold with my Euro-delivery 240D, to a neigbor. If I'd known that the car would eventually be stolen and torched, I would've hung on to it (along with a few other items)
My '84 Euro TD did come with a German folding triangle in a plastic case. And many years ago, I found a similar pair of cased German folding triangles in someone's curbside trash. Today, I carry them in my 240Ds. Too bad if they're not 'regulation-size'!

On a similar note, apparently the flash-to-pass headlight feature must hve been illegal here, as my '60 Fintail has the switch built into the turn-signal, but the wiring and relay aren't there.

Locally, here in Virgnia, Euro-headlights used to be prohibited by state safety inspection regulations. Many years ago, my Dad purchaed a Euro 250SE. A PO had installed the 'legal' US stacked sealed-beam headlights, but the first time we got the car inspected, the inspector made us remove the factory foglights, citing some rule prohibiting more than 4 headllights on a car!
However, I reinstalled them when my parents moved to Virginia Beach, and Dad never had any inspection issues there!

Many '50s imports, such as the VW Beetle and Morris Minor, used to have 'semaphore' turn-signal flags that would pop out from the door-posts. I would occasionally ask the owner of one of these cars why these items were broken-off or missing and was told that inspectors insisted the 'semaphores' had to be 'removed' to pass inspection.

Happy Motoring, Mark

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DrDKW