to make noise
A very small whistle, but with a loud sound
see the scale, you can easily blow in 3 or 4 copy of this whistle and make a lot of noise ...:D
The design is done to easily change the tone of the whistle with the thumb and index
3d model print parameters
any plastic, but be sure it's impervious, print at 100% fill density and at 0.1mm layer height if possible...