[qazwsxedchac]

These aren't Meccano, they are East German "Construction" sets. A riff on the Meccano idea, but metric, and probably not paying license fees to Meccano at the time ;-) The parts will look great quality while played with only a little, but the plating has a habit of coming off in small sharp flakes if you ever bend them.

[zvolsky]

Is it not Merkur?

The Czech version of the page says Frank Hornby patented the metal construction set in 1901. Merkur started just before the patent expired, long before the Cold War.

https://en.wikipedia.org/wiki/Merkur_(toy)

https://www.merkurtoys.cz/

[Waterluvian]

Thanks for the information! These were given to my dad in the 90s by a colleague at Environment Canada. Now I’m curious how they got here from East Germany.