HUL Prisma CPAP Filter retainer

The HUL Prisma CPAP machine has a set of two exchangeable filters sitting on the back of the device. Those filters are loosely placed in the filter frame and normally should stay there without a fixing mechanism. But my filters got blown out of the slot several times after coughing strongly in sleep. You will not be aware of the loss and thus may breeze dusty, unfiltered air for quite some time until you see they got blown out.  That can contaminate your machine with dust and there is no way for thee user to get the dust out again. 

To prevent that I designed this little retainer that is attached magnetically to the back of the Prisma machine. It is built this way so that it does not interfere with the airflow into the machine. Thanks to the magnet installation is easy and it can be removed for a filter exchange (or for transport). 
 

You will need a pair of 30x10x1mm magnets with adhesive tape on one side like this one (Amazon link, example): 

I printed it in PETG in two colors because I liked the colors. This is possible even without MMU just by changing the filament at a certain layer height. A monochrome print will work as good as the bicolor one and PLA will do the job of course, too. 
 

With this retainer I am sure now, my filters keep staying  in place under all circumstances. I hope other CPAP users find this little helper useful as well.

Please show me your results and send me fotos of your makes. I like to see how you use this model. If you have ideas for improvement don’t hesitate to send them to me in the comments.   I will try to incorporate your suggestions and will modify the model for special needs if you ask me to do so. 
And of course a like ♥ or a rating ⭐ of the design are always welcome. 

happy printing, clamikra