So Joseph Zisa is either refusing to share CAD files of his v29 whistle or doesn't have those.
So I decided to make my own based on his.

This one is created from scratch, I only used general idea of Joseph Zisa for that design.

Please note that the license is different for this one: it's GNU GPL v3.
The main difference is that if you remix this thing — remix have to be licensed on the same terms.

Shape Is a bit different and there is no internal ribs so you can print it much faster without loosing any function (probably shouldn't print this without infill).
And it can be much lighter, thus allowing it to naturally stay afloat if printed with less infill.
It doesn't need all that extra weight from redundant ribs v29 have.

The sources is there:
https://cad.onshape.com/documents/127002769eb5c2412870432a/w/84e3ee8687bc0f8d1c3acb2c/e/6e75b4f3ba9b11e85a305dd4

I printed and tested few.
In my ears it sounds way louder than v29.
Holy shit, it's ringing a lot.
Don't use it in enclosed room.

Also tested it outside.
Ears are ringing even though I was in open field.
Bloody ginger, it's freaking loud.

You are totally allowed to make unbranded version.
You are even allowed to put any text or logo on it, just don't claim the authorship.

Onshape guys are changing the interface often and export button for anonymous viewers not always works. If you need any source file but can't export it for some reason — feel free to ask me.

2 MMF mods: I am perfectly fine if someone rehosts this thing or it's remix as long as it honors the terms of GNU GPL v3 license.