I just noticed Christof's posted photos of what he called his personal pen of 2020. So I found the Indigraph website and found the concept very interesting.
https://indigraph.myshopify.com/pages/products
Explore the website pages and read about the design by Iñigo Echeverria.
https://indigraph.myshopify.com/pages/about-us
https://indigraph.myshopify.com/pages/faq
Interesting!
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