shower tub drain plug (baby bath tub) domoplex viega

This is a drain stopper i designed for my shower tub to turn it into a baby bath tub. I get about 10 to 15 cm which is enough for a baby bath. It does not hold the water perfectly but it stays overnight, so more than enough for a bath.
The plug.stl is what I designed regarding the technical data sheet, but it didn't fit for me. I made it a lot smaller in the slicer which resulted in 44.9x29.5 mm. In lack of a fitting o-ring i use a hair tie as seal.
It fits under the original lid which makes i