I’m unfamiliar with this drain line material (looks like electrical conduit but with rubber interior lining). It did have a trap inside (the sink was in a garage).
Looks like hose I use for my fish pond pumps to my filters .
Looks like a swimming pool vacuum hose.
Ahh, that’s it. Thanks!
There’s a good reason that you have not seen it used in this application before.
That’s funny! Yep!