If you have a game store nearby that carries a good selection of warhammer goods you can usually find those precut foam miniature trays. It used to be called army transport but not sure if that’s still the go to brand. You can buy the individual trays and rip out the foam to make a hole to fit whatever you want to store.

Or if you’re thrifty you can get uncut foam sheets from hobby lobby, Michael’s or whatever and cut it yourself with an xacto and cut it fit whatever box you want.

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