DIY Flutter Device to assist with clearing lungs

THIS IS NOT RECOMMENDED FOR USE AS A MEDICAL DEVICE. 3D prints can not be easily sterilized, and as such I cannot recommend using this long term. Versions of this device are available which are intended for long-term medical use - this is not one of them. I designed this model while stuck at home with COVID, to help with clearing mucous. Aside from being an exercise in copying an existing functional object, the purpose of this was to test the concept before paying for one and to use while waiting for that to arrive. It comes with two different tube lengths, two different lids with different levels of airflow, and four different sized balls which you can try to determine what works best for you. The balls, if printed at 100% infill, should work - but I recommend trying any marbles, ball bearings, or other heavy orbs you have at home as these will work much better.