All files are supportless prints.
Just for fun, have been creating magnetic boxes from terrain data. This one obviously is for the Grand Canyon. The lid is printed in this vertical position for maximum terrain definition/detail.
Comes with three different types of bottoms. One for games like D&D with an area for dice and other items, another that is split down the middle with a divider for any ranbom things, and one with just plain openness.
Examples printed at 0.2 mm line height and 15% infill. I would recommend not doing less than 15% infill, it prevents warping of the lid so that the tops and bottom fit together good.
Made for 6x3 mm magnets. I got some here for $14: