I use magnets to hold a mini warhammer 40k in a plastic case and on some model floors. This is the smallest ceramic magnet I've ever used and they have a much smaller field than I thought, which is good if you don't want all your pieces to accidentally stick together but seem a bit flimsy. I won't use them with more than a 30mm base because I wouldn't trust them. I like that ceramics add weight to the figures or I would use rare earth magnets.
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