I have never heard that name. Unfortunately the article does not seem to mention in what countries those kits were sold. Having grown up in Germany I remember

I have never heard that name. Unfortunately the article does not seem to mention in what countries those kits were sold. Having grown up in Germany I remember the name Kosmos. They seem to still exist. Not sure whether they were the most common / best ones. There is even a forum dedicated to the topic of electronic experimenting kits (in German): https://www.experimentierkasten-board.de/ https://www.experimentierkasten-board.de/ Edit: Based on http://www.elektronik-labor.de/Lernpakete/Ebaukaesten.html http://www.elektronik-labor.de/Lernpakete/Ebaukaesten.html I'd conclude that in the 1960s Kosmos was technically/didactically the leading one. In the 1970s probably surpassed by Philips. From the pictures I remember my friend had a Philips, the spring contact system was really good.