A really loud Whistle
thingiverse
You have to blow much more vigorously than a standard whistle, but don't be surprised if your hearing disappears the moment you do.
Download Model from thingiverse
With this file you will be able to print A really loud Whistle with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on A really loud Whistle.