This model is used to easily make sprue/vent cup containers for sand casting. You put this printed part with the large side down/post side up into a 32oz yogurt container (google “oikos 32oz” if you need a visual). Then, you mix play sand and sodium silicate (e.g. garage floor sealant, but has to be sodium silicate) in a separate container and then pack it in to the yogurt container with the part in it. When packed properly and given a day or so to set, it will result in the hardened sand cup pictured, and withstand the temperature of molten aluminum.