Avanti go cup plug

Hi this is the openscad files and stl for an avanti go cup plug - I washed mine down the sink since it was so little. I think it's designed to be a weak seal against spillage, but allow a pressure break if boiling water is sealed in the cup. It goes in the central hole (not the drinking hole) under the lid flap.

https://www.ozkitchenware.com.au/avanti-go-cup-double-wall-stainless-steel-insulated-cup.html