Portal - Level Warning Plaques REMIX (Magnets)

6mm x 2mm or 10mm x 3mm magnet holes. You can mix and match if you want. I found the 6x2 perfectly strong enough but I also have lots of 10x3 so I added those (very strong). They press-fit for me, but your mileage will vary. The 6x2 holes are 6.2mm in diameter but the 10x3 holes are 10.15mm in diameter.