The normal size is approx. 100mm high and has a wall thickness of 1mm. There is also a model with half thickness and a thinner base (to print at 150% size and above without spending 5 days to print). So you shouldn't need to use supports in your slicer. There are models with a base for easier printing and others with added integrated support for the underside of the loop (a thin membrane that you cut after printing). You will also find my SolidWorks 2017 source files (Quick and dirty + SW is not very happy with self-intersecting surfaces, I had to use a few tricks...) The latest and best models are named "EasyPrint" and print just fine without support. They also include a thicker "ceiling" in the top of the loop to avoid holes when printing. The teardrop hole makes it easier to start removing the support membrane with a knife.