The print profile is good and the part printed very cleanly and the supports came out without any issues. However, I don't think this is a practical design. The only way to make it practical is to make the part that goes into the bottle wider diameter and print it out of a relatively soft TPU. The other possibility is to make it so it fits on the outside of the bottle opening. The main issue is that I tried this on 4 different bottles and each had a slightly different inner diameter (even though the outer diameter and threads were the same. For some reason, there doesn't seem to be any standards for the ID of the bottles. So, I printed a couple at different scaling but quickly came to the conclusion that this is one type of printed solution that's not worth the effort. By the time I figure out all the right sizes I would have to print a dozen of these and spend literally half a day or more. I ended up buying a dozen of them from Amazon for $8. They have soft silicon material.

I printed bunch of these but I had to scale the main part down a bit so that when the other part is inserted, the fit is tight. The cutting teeth need to be more aggressive though. I had trouble cutting even a normal masking tape with it. I have seen other designs with much more prominent teeth but the designs are bulkier. Honestly, I couldn't find any solutions out there that are worth the effort.