I designed these Catan game piece holders to be the exact size of a normal Catan hex (from my Catan Fifth Edition). They have slots in the bottom for 6mm x 2mm magnets so that they can be connected to each other (I personally used Neodymium magnets and they work well, I also superglued them in). I have made piece holders for base Catan, Seafarers, Cities & Knights, Traders & Barbarians, and Explorers & Pirates. I do plan on making holders for some of the scenarios, stories, and promos, eventually.
The author hasn't provided the model origin yet.