Just a 50mm Don't panic button /badge - swap filament for the top 3 layers for dual colour.
I have added magbutton.stl - this version has a 10x1mm hollow inside - with layer heights all at 0.2 , pause at layer 9 - place a 10x1mm magnet and resume printing. Filament change at layer 26 to get a two colour badge.
Brass nozzle only when using strong neodymium magnets.
I tried the magbutton version but the hollow proved a bit small for the 10x1mm magnet - Will try 103% scaling to see if it fits.
New Magnet Button2.stl - 10x1mm magnet fits perfectly - filament change should be at layer 27

• I got it a bit wrong so my colours are not as intended
• the small cylinder is a blob catcher for the coulour change