The orignal case was huge for me, thats why I designed a much smaller one. As the filters are magnetic, I used 3 washers inside the model thats why the filters snap into the place. Just pause the print in a specified layer, and put in the metal parts.
The washer's parameter (which I had a lot of at home):
OD: 16mm 5mm
ID: 5mm
Thikness: 1mm
The numbers simply painted with permanent marker.
The letters in the lid are different parts, can be printed from a different color, then glue … or just leave debossed.
The author marked this model as their own original creation.