The model requires by default an 1x8mm magnet but you can change this easily in the provided fusion file. You can always secure the magnet in place with a little bit of glue but it should be a press fit.
Note that if you want to obtain the base voronoi model you can simply split the model to its parts (but you shouldn't otherwise)
Printing Information:
The author remixed this model.
I applied a voronoi technique to the base model and added a magnet holder piece