I guess my knowledge of cars must have atrophied…

Not so sure about that, given that I’m pretty sure there’s a full sized Mercedes in the back row, and what to me looks like a Volvo in the middle slot, facing the camera.

You assume I’m ever “about in public”?

Rough guess works be 20cm diameter, so 16% of the force required.

And as opposed to the Magdebutger hemispheres, these objects don’t come with handles for good grip.

@FreeBeard separates evacuated Magdeburger hemispheres by hand.

/s

https://en.m.wikipedia.org/wiki/Magdeburg_hemispheres

Swedish. Of course, these all lack three letters. And I don’t think this tool counts special characters?