Quote Originally Posted by OngBonga View Post
hmm interesting. Those bungs clearly go into test tubes, but I can't find similar images by googling.

I'll keep digging, I'll find a good resource sooner or later.
The shape of it reminds me of the sewer traps you see under any plumbing drain. Their purpose is to trap the stank sewer gas behind that fluid blockage that collects in the bend.