This is a basic sliding dishwasher sign to show whether your dishes are dirty or clean, just flip the sign when you start the dishwasher and whoever walks by next will know your dishes are clean!
This uses a snap-on slider, and uses pause-on-layer to allow you to insert four 6x3mm round magnets, and a second layer change to make the words stand out.
I used magnets from aliexpress, listings come and go, so search for "6x3mm magnet" and you should find plenty of options.
https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20200917062118&SearchText=6x3mm+magnet
This was designed explicitly for 3d printing with no need for support and minimal overhangs. I do recommend a cooling fan for the overhangs though.
The author hasn't provided the model origin yet.