The Air intake on S1 and S1Pro is on the top of the machine
this is a risk for sucking in dust
due to the higher flow rates of those used CPAP Fans the airstream is also potentially a risk for sucking in unwanted particles
therefore i bought a cheap filter on aliexpress:
https://s.click.aliexpress.com/e/_olOMWaN
i picked the 60mm version
additionally i printed this small ring with some 6x3mm Magnets
Part on the picture is made with PETG, a quick 12 minute print on those machines
Just plug in the Magnets and fit the part to the rubber piece of the Filter
Place that on the CPAP Inlet and you are done
The author marked this model as their own original creation.